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Objectives : The knowledge about outcomes of infant vaccination against HBV infections using the DPT-HepB-Hib vaccine in Ghana is limited. This study therefore investigated the levels of immunity to HBV among children who received the DPT-HepB-Hib vaccine and HBsAg carriage in non-responders. Correlates for non-response or poor response were also investigated. Methods : Cross-sectional study. A major paediatric hospital in Accra. Four hundred and twenty four children between the ages of 5 to 32 months who had completed the full vaccination schedule for the DPT-HepB-Hib vaccine. Results : Of the 424 children, 358 (84.4%) developed anti-HBs while 340 (80.2%) developed ≥10 mIU/ml anti-HBs (sero-protection) and 3 had HBsAg. A binary logistic regression analysis showed that younger children were associated with sero-conversion (p=.022) and sero-protection (p=.021). For anti-HBs titres ≥100 mIU/ml age was a weaker but significant contributor (p=.041), as compared to the number of vaccines from different manufacturers the child used (p=.028). The mean age of those who used a single type of vaccine was higher (14.75 ± 6.056 months; n=268) than those who used vaccines from two or more manufacturers (11.96 ± 4.645 months; n=156), p=

Consumers perceive packaged drinking water, usually distributed as bottled or in polyethylene packages (sachets), as healthier and safer alternatives to tap water. The objective of this study was to determine the microbiological quality of different types of packaged drinking water available in Accra, Ghana. Sixty samples of sachet water and ten of (PET) bottled water were randomly purchased from various locations in Accra. Bacteriological and parasitological analyses of the packaged (sachet and bottled) and tap water (as control) were done according to standard procedures. Fifty-two out of 60 sachet water samples (86.7%) had HPC levels well above the internationally recommended limits. For the bottled water, nine out of the ten (90%) were within the recommended limits for HPC. Two out of the five (40%) tap water samples (control samples) had HPC above the recommended limits of 500 cfu/mL. While none of the bottled water samples showed the presence of protozoa, two out of the five tap water and 31 out of the 60 sachet water samples had a wide range of protozoa including rotifers. The findings clearly indicate that while PET bottled water sold in Accra may be generally safe, the same cannot be said for the sachet water; since the study found its microbiological quality not significantly different from tap water.

Background Co-infection of HIV with HBV is common in West Africa but little information is available on the effects of HBV on short-term therapy for HIV patients. A 28 day longitudinal study was conducted to examine short-term antiretroviral therapy (ART) outcomes in HIV infected individuals with HBV co-infection. Methods Plasma from 18 HIV infected individuals co-infected with HBV and matched controls with only HIV infection were obtained at initiation, and 7 and 28 days after ART. HIV-1 viral load changes were monitored. Clinical and demographic data were also obtained from patient folders, and HIV-1 drug resistance mutation and subtype analysis performed. Results The presence of HBV co-infection did not significantly affect HIV-1 viral load changes within 7 or 28 days. The CD4+ counts on the other hand of patients significantly affected the magnitude of HIV-1 viral load decline after 7 days (ρ = −0.441, p = 0.040), while the pre-ART HIV-1 VL (ρ = 0.844, p =

Introduction: Vaccination is the most effective preventive strategy against rotavirus disease. Regional differences in prevalent rotavirus genotypes may affect vaccine efficacy. Pre-vaccine surveillance for burden of rotavirus disease, prevalent rotavirus genotypes, and association between rotavirus disease and intussusceptions helps in monitoring the impact of vaccination. Methodology: A prospective study was conducted from January 2008 to December 2009 in children younger than five years hospitalized for longer than 24 hours with acute gastroenteritis. Data on confirmed cases of intussusception were collected retrospectively. Stools were tested by enzyme immunoassay, reverse-transcriptase polymerase chain reaction and nucleotide sequencing. Results: Acute gastroenteritis (AGE) caused 13.1% (2,147/16,348) of hospitalizations among children under five years. Stools were tested for 50.2% (1077/2147) of AGE cases. Of these, 49% (528/1077) were rotavirus positive. Rotavirus gastroenteritis, non-rotavirus gastroenteritis, and intussusceptions were most prevalent in children under 15 months [80.3%, 74% and 91% respectively]. Rotavirus was detected from more than 60% of acute gastroenteritis cases during peak months. The prevalence of intussusception showed no seasonal pattern. The peak ages of six to twelve months for acute gastroenteritis and five to eight months for intussusception overlapped. G1, G2 and mixed G/P genotypes were common in the isolated rotaviruses. Conclusion: Rotavirus gastroenteritis causes significant morbidity in children younger than five years of age in Ghana. Although the peak age of rotavirus gastroenteritis and intussusceptions overlapped, there was no seasonal correlation between them. The high prevalence of mixed G/P genotypes in Ghanaian children may affect the effectiveness of vaccination.

Data on the effects of the presence of hepatitis B virus (HBV) and hepatitis C virus (HCV) in patients co-infected with these viruses and HIV in West Africa are conflicting and little information is available in Ghana. A cohort of 138 treatment naïve individuals infected with HIV was screened for HBV and HCV serologic markers; HBsAg positive patients were tested for HBeAg, anti-HBe, and anti-HBc IgM. The viral load of HIV-1 in the plasma was determined in 81 patients. Eighteen of the 138 patients (13%) and 5 (3.6%) had HBsAg and anti-HCV, respectively. None of the patients had anti-HBc IgM, but 10 (55.6%) and 8 (44.4%) of the 18 patients who were HBsAg positive had HBeAg and anti-HBe, respectively. In patients with measurement of CD4(+) undertaken within 1 month (n = 83), CD4(+) count was significantly lower in patients with HBeAg (median [IQR], 81 [22-144]) as compared to those with anti-HBe (median [IQR], 210 [197-222]) (P = 0.002, CI: -96.46 to 51.21). However, those with HIV mono-infection had similar CD4(+) counts (median [IQR], 57 [14-159]) compared to those with HBeAg (P = 1.0, CI: -71.75 to 73.66). Similar results were obtained if CD4(+) count was measured within 2 months prior to initiation of HAART (n = 119). Generally, HBV and anti-HCV did not affect CD4(+) and viral loads of HIV-1 in plasma but patients with HIV and HBV co-infection who had HBeAg had more severe immune suppression as compared to those with anti-HBe. This may have implication for initiating HAART in HBV endemic areas.

Viral decay rates during efavirenz-based therapy were compared between human immunodeficiency virus (HIV)-infected patients without tuberculosis (n = 40) and those with tuberculosis coinfection who were receiving concurrent antituberculous therapy (n = 34). Phase I and II viral decay rates were similar in the 2 groups (P > .05). Overall, concurrent antituberculous therapy did not reduce the efficacy of the HIV treatment.

Serologic screening for antibodies to the acquired immunodeficiency syndrome (AIDS) virus human immunodeficiency virus (HIV) has been carried out in Ghana since 1986 when the 1st AIDS case was detected. In general surveys have indicated a low HIV-1 seroprevalence rate among the general population. Of 1852 blood donors screened in 1986 only 2 (0.1%) were positive. None of 168 laboratory workers screened at the same time was seropositive. Also demonstrated has been a relatively low (2.1%) seroprevalence rate among local prostitutes in Accra. However of 151 Ghanaian women who worked as prostitutes in the Ivory Coast 49% were HIV-1 seropositive upon their return to Ghana. Similarly 215 males and females from the general population who had spent time living in the Ivory Coast and other West African countries such as Burkina Faso were found to be seropositive. In all 212 Ghanians have been tested as seropositive for HIV infection in the March 1986-July 1987 period. The greatest number of cases have been reported from Ghanas Eastern Region Greater Accra and Ashanti. The male to female ratio of HIV-positive cases was 1 to 11.6 in 1986 and 1 to 6.3 in 1987. The predominant presenting complaints of AIDS patients in Ghana are weight loss (89%) persistent or intermittent diarrhea (78%) respiratory symptoms (67%) fever and night sweats (56%) and central nervous system symptoms (50%). It is believed that more than 50% of prostitutes in the Ivory Coast are from Ghana. Many of these women return to their home country for holidays or to seek medical care when they develop symptoms of HIV infection. Unless effective intervention is implemented to limit the heterosexual spread of AIDS in Ghana its incidence may soon become as high as it is in Central Africa.

775 G H AN A A N D IV ORY COAS T are situated between the two major initial foci of the African HIV-1 and HIV-2 epidemics. It is in such countries that dual HIV-1/HIV-2 serological reactivity (dual seropositivity) is most common. The proportion of dual seropositivity has increased in West Africa countries, where HIV-2 was initially the main cause of the epidemic. The diagnosis of dual HIV-1/HIV-2 infections may be complicated, as HIV-2 DNA cannot always be detected and the levels of HIV-2 DNA in dual seropositives may decrease with progression to AIDS. Also, even low levels of HIV-2 antibodies can imply dual infection. 4 The lack of HIV-2 DNA and/or low HIV2 antibody level may thus be related not only to the diagnostic methods used, but possibly to suppression of HIV-2 by HIV-1. HIV-2 infection may protect against HIV-1 superinfection, which could have impact on the development of protective vaccines. It has been suggested that the HIV-2 protection from subsequent HIV-1 infection is mediated by b -chemokines and CD8 1 cells, and is restricted to HIV-1 strains using the CCR5 receptor. Furthermore, conflicting reports on cross-neutralization of HIV-1 isolates by HIV-2 sera exist. Since the V3 loops of the viruses are important for chemokine receptor usage and neutralization, a critical look at this region is of interest for understanding the interaction between HIV-1 and HIV-2 in vivo. We therefore determined the V3 sequences of HIV-1 strains obtained from epidemiologicall y matched patients seropositive for both types or HIV-1 only. Peripheral blood mononuclear cells (PBMCs) were obtained from patients who were HIV seropositive by World Health Organization (WHO) criteria (Table 1), attending semi rural or urban AIDS clinics in the southern part of Ghana during 1996. Ethical permission was obtained from the Ministry of Health (Accra, Ghana), the University of Ghana Medical School (Accra, Ghana), and the Huddinge Hospital (Huddinge/ Stockholm, Sweden). Lymphocyte subset determination was performed by a flow cytometric method and the patients classfied as asymptomatic or symptomatic on the basis of the WHO expanded clinical definition of AIDS. Two commercial kits were used for analysis of anti-HIV reactivity. In brief, a dot immunobinding assay (Target HIV1-HIV2; V-Tech, Pomona, CA), which is based on homologous synthetic peptides in the HIV-1 and HIV2 transmembrane proteins, was used for screening. Confirmatory tests with a line immunoassay including recombinant proteins and peptides for HIV-1, and a peptide for HIV-2 (Innolia; NV Innogenetics, Antwerp, Belgium), were done according to the manufacturer instructions. Samples that reacted with HIV1 gp41 (and other bands) with a rating of 1 1 or above were considered HIV-1 seropositive, and those having additional reactivities of at least 11 with the HIV-2 gp36 band were classified as dual seropositive. Two million PBMCs were lysed and DNA was extracted by phenol±chloroform and ethanol precipitation. To amplify an env fragment encoding the V3 loop, the following outer primers were used: JA 167 [5 9 TAT C(C/T)T TTG AGC CAA TTC C(C/T)A TAC A] and JA 170 [5 9 GTG ATG TAT T(A/G)C A(A/G)T AGA AAA ATT C], with conditions previously described. For the nested step, primers V3-3 (59 biotin-AATGGCAGTCTAGCAGAA) and V3-4-M13 (5 9 M13-CTGGGTCCCCTCCTGAGG) were used. Direct sequencing was performed using magnetic beads with covalently coupled streptavidin (Dynabeads, M280-streptivid in; Dynal A.S., Oslo, Norway), an AutoRead sequencing kit (Pharmacia Biotech, Uppsala, Sweden), and an automated laser fluorescence sequencer (ALFexpress; Pharmacia Biotech). Sequences approximately 252 or 249 nucleotides long were manually aligned. The phylogenetic analysis was done with the TREEDON package and 1000 bootstrap resamplings. Distance calculations were derived by neighbor joining, using the Jin and Nei method ( g distribu

Until recently, HTLV-I was considered to be an Old World virus and HTLV-II was thought to be endemic in the Americas. However, the presence of HTLV-II among Pygmies and other populations of Africa has raised doubts as to whether HTLV-II is primarily a New World virus. The large serosurveys conducted in the urban and rural areas of southern Ghana have identified a 1-2% prevalence for HTLV-I/II. To define the HTLV type, we have used a Western blot assay (HTLV-2.3 blot) that allows simultaneous confirmation and differentiation between HTLVs. Samples (n = 139) were chosen on the basis of previous reactivity with either an enzyme immune assay or r21e-spiked WB results. The WB 2.3 analysis of these specimens identified 55 (40%) to be HTLV positive, 70 (50%) to be HTLV indeterminant, and 14 (10%) to be HTLV negative for HTLV. HTLV seroindeterminant patterns ranged from both gag and env (14 were r21+, p24+, and/or p19+ [all were RIPA negative]) to gag only (21 were p24+/p19+, 16 were p19+, and 7 were p24+), and env only (8 were r21+ and 4 were rgp46+) reactivities. Of the 55 HTLV-positive specimens, 41 were typed as HTLV-I, 9 were HTLV-II, and 5 could not be typed (HTLV-I/II). Of the nine HTLV-II-positive specimens, three were from patients with Burkitt's lymphoma and six were from healthy individuals (two pregnant women) with no obvious risk factors for HTLV-II.(ABSTRACT TRUNCATED AT 250 WORDS)

Human rotavirus (HRV) infection and its seasonal distribution was studied over a 12-month period in Ghana. A total of 561 stool samples, 447 diarrhoea stools and 114 non-diarrhoea stools (controls), were obtained from children attending three polyclinics in Accra. Rotavirus was detected during 10 of the 12 months and showed a seasonal trend. It was high during the relatively cool dry months and low during the wet season. Peaks of infection were in February (26.2%) and September (24.5%). HRV was detected in 67 of 447 of the diarrhoea stools (15.0%) and in eight of 114 controls (7.0%). The HRV isolation rate was highest (20.2%) in the under-18-months age group. The RNA electropherotype of the HRV isolates was predominantly (83.6%) of the long type. Non-group A HRV was detected in 14.9% of the HRV-positive samples.

Objective: To determine the correlates of hepatitis E virus infection (HEV) in a sample of persons who work with pigs. Design: Cross-sectional study. Setting: Three pig farms in the Greater Accra Region of Ghana. Subjects: Persons who work with pigs seen at the selected pig farms between the months of January and May 2008. Results: One hundred and five persons who work with pigs voluntarily completed a risk-factor questionnaire and provided blood samples for unlinked anonymous testing for the presence of antibodies to HEV. The median age of participants was 36.5 ± 15.0 years (range 12-65 years). Of the 105 subjects tested, HEV seroprevelance was 38.1%. On multivariate analysis, the independent determinants of HEV infection were being employed on the farm for less than six months (odds ratio (OR) 9.1; 95% confidence interval (95% CI) 1.0-81.4 and having piped water in the household and/or on the farm (OR 3.9; 95% CI 0.4-90.8). Conclusion: Consistent with similar studies worldwide, the results of our studies revealed a high prevalence of HEV infection in persons who work with pigs. Further studies need to be done to isolate, characterise the virus and define the clinical and epidemiological significance of HEV infection in this population.

Background: The presence of dual HlV-l/HIV-2 infection in Ghana and the different drug requirements for the treatment of HlV-1 and HIV-2 presents difficulties for the treatment of dual infections with both viruses. Objectives: To determine the prevalence of the dual sero-positive profile in treatment naive patients at a principal ART Clinic in Accra, Ghana and to investigate if rapid screening assays could be useful for diagnosis. Design: A cross-sectional study. Setting: A principal antiretroviral treatment centre in Accra, Ghana. Subjects: Three hundred and twenty eight antiretroviral treatment naive patients. Results: A total of 12 (3.7%) of patients seen were dual seropositive. There was a slight tendency of dual seropositive females being older than their HIV-l counterparts (p=0.088, CI=-l 0.833 to 0.753). Eight of the 12 of the dual seropositives were reactive for Genie II and were considered as possibly infected with both HIV-I and HIV-2. Seven (87.5%) of Genie II dual seropositives had strong intensities (> 1+) on both HIV-2 specific bands (sgp105 and gp36) on Innolia. CD4 counts were not significantly different in dual seropositives as compared to HIV-1 infected patients. Conclusions: Dual HIV-l/HIV-2 seropositives (and possibly infections) may be common especially in older women. The Genie II will be useful as a supplemental rapid test for rapid and accurate differentiation of HIV-l and HIV-2 antibodies at treatment centres.

A rapid immunobinding assay ('HIVCHEK', Ortho) and an agglutination assay ('Serodia-HIV', Fujirebio) were evaluated as an alternative to enzyme-linked immunosorbent assay (ELISA) and western blot under field conditions in Africa for detection of antibody to human immunodeficiency virus (HIV). 7106 specimens were tested at 25 laboratories in Kenya, Ghana, Senegal, and Zaire. HIVCHEK was used as a screening test, and serodia-HIV as a supplemental test to evaluate these assays in an alternative testing strategy to the standard ELISA/ western blot testing procedure. In each country, HIVCHEK was more sensitive and specific than ELISA when compared with western blot. The sensitivity of HIVCHEK ranged from 87·0 to 96·3% and the specificity from 99·0 to 100%. The sensitivity and specificity of serodia-HIV ranged from 85 to 98% and from 88 to 98%, respectively. The sensitivity and specificity were affected by the presence of HIV-2 in Ghana and Senegal. Overall, with an HIV-1 prevalence of 14·8% in Kenya and 22·5% in Zaire, the sensitivities of the alternative strategy were 96·4% and 91·4%, the specificities 99·6% and 100%, the positive predictive values 97·6% and 100%, and the negative predictive values 99·3% and 97·9% for Kenya and Zaire, respectively. With this testing format there was an estimated average cost saving of up to 82% over the conventional strategy with ELISA/western blot. This procedure constitutes a reasonable alternative to the standard ELISA/ western blot combination.

Objectives: Areas with high HIV-incidence rates compared to the developed world may benefit from additional testing in blood banks and may show more favorable cost-effectiveness ratios. We evaluated the cost-effectiveness of adding p24 antigen, mini pool nucleic acid amplification testing (MP-NAT), or individual donation NAT (ID-NAT) to the HIV-antibody screening at the Korle Bu Teaching Hospital (Accra, Ghana), where currently only HIV-antibody screening is undertaken.Methods: The residual risk of HIV transmission was derived from blood donations to the blood bank of the Korle Bu Teaching Hospital in 2004. Remaining life expectancies of patients receiving blood transfusion were estimated using the World Health Organization life expectancies. Cost-effectiveness ratios for adding the tests to HIV-antibody screening only were determined using a decision tree model and a Markov model for HIV.Results: The prevalence of HIV was estimated at 1.51% in 18,714 donations during 2004. The incremental cost per disability-adjusted life-year (DALY) averted was US$1237 for p24 antigen, US$3142 for MP-NAT and US$7695 compared to the next least expensive strategy. HIV-antibody screening itself was cost-saving compared to no screening at all, gaining US$73.85 and averting 0.86 DALY per transfused patient. Up to a willingness-to-pay of US$2736 per DALY averted, HIV-antibody screening without additional testing was the most cost-effective strategy. Over a willingness-to-pay of US$11,828 per DALY averted, ID-NAT was significantly more cost-effective than the other strategies.Conclusions: Adding p24 antigen, MP-NAT, or ID-NAT to the current antibody screening cannot be regarded as a cost-effective health-care intervention for Ghana.

Human herpesvirus-6 (HHV-6) infection seems to be ubiquitous early in life, but antibody responses vary by geographic area. We compared HHV-6 antibody titer in 123 West African and 122 Caribbean serum samples. A quantitative immunofluorescence assay (IFA) using antigens derived from an HSB-2 cell line was used to test for IgG HHV-6 (GS strain) antibodies. The prevalence of HHV-6 antibodies was high (98%) in both sites. African samples had a significantly higher geometric mean titer (GMT: 697) than did Caribbean samples (GMT: 99). There was no difference between males (GMT: 260) and females (GMT: 270) overall. Children up to and including 9 years old had significantly higher titers (GMT: 483) than did all others (GMT: 237), and female children tended to have higher titers than did male children. In both areas there was a trend towards highest titer at younger age, followed by a decrease in titer during adulthood and middle age, and a secondary rise in titer in the oldest age group. Environmental and host factors may explain these geographic differences in antibody responses between two groups of African origin.

A highly divergent HIV-2 designated as HIV-2[GH-2] was obtained from an AIDS-related complex (ARC) patient in Ghana. A full-length molecular clone of this isolate was obtained and a biologically active clone was constructed. Its restriction pattern differed from that of prototype HIV-2[GH-1] in 25 of 35 restriction sites, but was strikingly similar to a previously characterized HIV-2 isolate from a Ghanaian (HIV-2ALT). The conserved integrase region (288-bp fragment) previously displayed 95% identity with that of ALT but 17-20% divergence from the HIV-2 prototype member, and a new distinct subgroup (HIV-2b) of HIV-2 consisting of GH-2 and ALT was postulated (Miura et al. 1991.) These isolates, however, were biologically distinguishable from each other by its replication capacity in a monocyte line, U937, in which GH-2 could not grow but ALT grew well. In addition, the nucleotide sequence of the LTR of this new isolate displays 21% divergence from that of prototype HIV-2[GH-1], but the core enhancer, Sp1 binding sites and TATA box were conserved. Although the 3' half of the env gene sequence which is deleted in HIV-2ALT clone showed 27% diversity from the prototype, functional differences in the rev-responsive element were not observed.

Background Hepatitis E virus (HEV) is highly endemic in several African countries with high mortality rate among pregnant women. The prevalence of antibodies to HEV in Ghana is not known. Therefore we evaluated the prevalence of anti-HEV IgG and anti-HEV IgM among pregnant women seen between the months of January and May, 2008 at the Obstetrics and Gynaecology Department, Korle-Bu Teaching Hospital, Accra, Ghana. Results One hundred and fifty-seven women provided blood samples for unlinked anonymous testing for the presence of antibodies to HEV. The median age of participants was 28.89 ± 5.76 years (range 13–42 years). Of the 157 women tested, HEV seroprevelance was 28.66% (45/157). Among the seropositive women, 64.40% (29/45) tested positive for anti-HEV IgM while 35.60% (16/45) tested positive to HEV IgG antibodies. HEV seroprevalence was highest (46.15%) among women 21–25 years of age, followed by 42.82% in = 20 year group, then 36.84% in = 36 year group. Of the 157 women, 75.79% and 22.92% were in their third and second trimesters of pregnancy, respectively. Anti-HEV antibodies detected in women in their third trimester of pregnancy (30.25%) was significantly higher, P < 0.05, than in women in their second trimester of pregnancy (25.0%). Conclusion Consistent with similar studies worldwide, the results of our studies revealed a high prevalence of HEV infection in pregnant women.

We designed a universal primer (UNIPOL) for DNA amplification of AIDS-related viruses. The phylogenetic tree constructed from the presumed sequences amplified with UNIPOL was representative of the tree calculated from whole pol gene sequences so far reported. UNIPOL was able to amplify the sequences of all four major groups of primate lentiviruses and also that of a distinct virus from a Ghanaian patient with an AIDS-related complex, designated GH-2. This strain scarcely hybridizes with known HIV/simian immunodeficiency virus (SIV) DNA probes. Sequence analysis of the only amplified fragment revealed rapidly that GH-2 was quite similar to the recently reported HIV-2ALT(D205) and that these two viruses form a new subgroup distint from known HIV-2 and SIVmac/SIVsm in the large HIV-2 group. This system will be useful for further phylogenetic study of various primate lentiviruses.

SUMMARYChildren in a village in rural Ghana were found to have acquired antibody to rotavirus by the age of two years. The results of our study suggest that primary infection takes place early in infancy. Fifty-six per cent of the three to 20-months-old had a four-fold rise in antibody levels during the six months follow-up period and 72.2% of them had one or more episodes of diarrhoea compared with 42.8% of those whose antibody levels stayed the same or decreased. The major epidemic season is considered to be the dry season.

Two isolates of human T-cell leukemia virus type I (HTLV-I) were obtained from lymphocyte cultures of a healthy carrier in Gabon and another in Ghana. Their proviruses were analyzed by Southern blot hybridization and compared with prototypical HTLV-I isolated in Japan and the United States. The provirus genomes of both strains were highly homologous to the prototype HTLV-I along the whole viral genome. The restriction endonuclease sites of the Ghanian isolate were almost identical with those of the prototype HTLV-I, but 10 of 26 sites of the Gabonese isolate were different from those of the prototype. Furthermore, the restriction map of the Gabonese isolate resembled those of a simian T-cell leukemia virus (STLV-I) isolated from a chimpanzee from Sierra Leone and a variant of HTLV-I from Zaire (HTLV-Ib) more closely than those of any other known HTLV-I. These results indicated the existence of some unique strains of HTLV-I transmitted among African people, and the importance of clarifying the origin and transmission of HTLV group viruses.

Measles has been one of the most important childhood diseases in tropical areas not only as the main causes of mortality and morbidity but also as an important cause of diarrhea and malnutrition. The problem with measles vaccination in tropical areas is the blocking effect of maternal antibody in infants because children in tropical areas are immunized as soon as possible to minimize morbidity under 1 year of age. The objective of this study is to clarify the situation of measles in Ghana and to try an alternative way of immunization. Active surveillance of villagers has been done since 1982 in a rural area of Ghana. There were epidemics of measles twice in each dry season and 29 children suffered measles. Many children (45%) were less than 1 year old. The transplacental maternal HI antibody against measles was found to have disappeared by 6 months of age although the antibody level of mothers was not low. Vaccination has been carried out with 3 kinds of measles vaccine strains. It may be possible to start immunization against measles at the age of 6 months with subcutaneous injection. The inhalation of aerosolized measles vaccine has also been done. Seroconversion rate was not so good but the mean HI antibody titer was higher than by subcutaneous injection. A further study is going on now to immunize children aged 3 months to 11 months by both subcutaneous injection and inhalation of aerosolized measles vaccine using a mask.

One hundred and thirty-nine bovine sera collected in Senegal in 1968 and 1969, before the human pandemic of acute hemorrhagic conjunctivitis (AHC), and 145 sera collected in 1977, seven years after the introduction of AHC, were tested for virus neutralizing (VN) titers against enterovirus 70 (EV70) in neutralization tests. Positive rates of VN titers (1:16) were fairly constant (about 40%) in 1968 and 1969 but the proportion of positives from the 1977 collection was significantly higher (61%). The proportion of Ghanaian bovine sera positive in 1977 (39%) was comparable with those collected earlier in Senegal but the proportion was lower in sera of calves (7%). Similar studies were performed on sheep sera collected in 1966, 1967, 1968, and 1969 in Senegal. The proportions positive and the geometric mean titers (GMTs) peaked in alternate years: the proportions were 43% and 54% in 1966 and 1968 but dropped to 12% and 5% in 1967 and 1969, respectively. The prevalence rate for Ghanaian sheep sera in 1977 was comparable to the earlier figures in Senegal. The prevalence of VN (83%) and the GMT (1:27.28) in swine sera in Ghana in 1977 were much higher than those seen in chickens and dogs. However, 87 sera of wild monkeys caught in Senegal after 1970 were negative in neutralization tests. The VN substance detected in these domestic animals was found to be 2-mercaptoethanol sensitive; hence it is considered to belong to IgM. The results seem to favor the hypothesis that enterovirus type 70 (EV70) evolved from an animal enterovirus which shares a common antigen with EV70.

Data on the seroepidemiology of rubella in tropical Africa have been scarce. However, reports of serologic surveys in many countries within the last few years have changed this situation. Studies in Angola have shown an overall rate of positivity for rubella antibodies of 73% among females between the ages of 15 and 19 years. In the group between five and nine years of age, 74% had rubella antibodies. Therefore, Angolans acquired natural immunity before beginning school. In Ghana, greater than 70% of women of childbearing age had rubella antibodies, and in Nigeria 60% had antibodies. In The Gambia, by 14 years of age, 93% or more of the female population had immunity to rubella. Similar high levels were found in surveys conducted in Ethiopia, Upper Volta, and Uganda. However, a low level of 33% was recorded in Togo. The reports indicate that rubella infection is widespread and endemic on the African continent.

To learn more about the relative prevalence of viruses from the human immunodeficiency virus (HIV)/simian immunodeficiency virus (SIV) groups in Ghana, serum samples were collected in 1986 from 47 men and women with acquired immunodeficiency syndrome (AIDS) or AIDS-related complex (ARC), 57 apparently healthy individuals, and 11 AIDS-free hospital inpatients. Western blot analysis revealed a total of 46 reactive sera. 43 of the 47 serum samples from those with AIDS or ARC were positive; 6 were seropositive for HIV-1, 18 for HIV-2, 17 for both HIV-1 and HIV-2, and the remaining 2 were not reactive with glycoproteins. Of the 2/10 individuals with mild symptoms of HIV infection who proved to be seropositive, 1 was positive for HIV-2 and 1 for HIV-1 and HIV-2. There were no seropositive reactions among the AIDS-free hospital patients, and only 1 such reaction (seropositive for HIV-2) among the healthy individuals. These findings indicate that both HIV-1 (6 cases in this series) and HIV-2 (20 cases) are responsible for the development of AIDS in Ghana, and that there is a high prevalence (18 cases) of cross-reactivity between the 2 viruses. There was no evidence of SIV infection. Further research is needed to determine whether these findings are a result of cross-reactivity between envelope proteins of HIV-1 and HIV-2, double infection of AIDS patients, or infection with a new variant strain. Since prostitutes comprised 25 of the 47 AIDS/ARC patients and 6 of the 10 with mild symptoms of HIV infection, they are an important target for preventive efforts.

The isolation of simian immunodeficiency virus (SIV) from African non-human primates and 2 new human retroviruses from people in West Africa (HIV-2 and HTLV-IV) which are antigenically closely related to SIV indicate the importance of viral ecological studies on HIV/SIV especially in Africa. This is a report on reactivity with the antigens of SIV derived from African green monkey and HIV-1 of antibodies in 29 anti-HIV-positive human sera from East and West Africa. SIV shares antigenicity with the gag gene products of HIV-1 but not with its envelope gene protein products. Of the 29 sera 12 were from patients with AIDS or AIDS-related complex (ARC) in Kenya 5 from apparently healthy people in Gabon and 12 from prostitutes manifesting ARC in Ghana. From the serological findings it is conceivable that the antibody-positive people in Kenya are infected with a virus that is antigernically similar to prototype HIV (HIV-1) while those in Gabon and Ghana are infected with a virus that is closely related to SIV such as GTLV-IV or or HIV-2. To test this idea isolates from these seropositive persons were obtained in Kenya and Ghana. Analysis of viral proteins and genomes revealed that the Kenyan isolates were indistinguishable from the prototype HIV-1 group whereas the Ghanaian isolate belongs to the HIV-2 virus group.