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A cross-sectional study was performed in 60 Cuban women of child-bearing age who were seropositive for human immunodeficiency virus (HIV) and 60 controls. Human papillomavirus (HPV) was identified most frequently, with oncogenic HPV serotypes 16, 33 and 58 detected in HIV-positive patients, and serotypes 11, 33 and 51 in the controls (relative risk 4.41; 95% CI 2.21–8.29). Syphilis and hepatitis B and C viruses were detected exclusively in HIV-seropositive women (p < 0.05). Sexually transmitted diseases (STDs) appeared to pose a substantial health problem, especially for HIV-positive women. Clinics should consider screening and treatment for STDs as part of their HIV prevention programmes. [ABSTRACT FROM AUTHOR]

With the objective of increasing the immune response to the HBsAg we have used the Cuban anti-hepatitis B immunoglobulin in human chronic reservoirs of the virus. The great neutralizing activity of the product allows us to propose it as a diagnosing element where doubts exist in the interpretation of the analytic base, using it on patients who do not have enough criteria to classify them as reservoir or immune. This also allows us to propose it for prophylactic use in liver transplant for HBV. To measure the titles of obtained antibodies we used the double-antigen Sandwich-type quantitative enzymatic immunoassay developed by the Department of Immunology of the ICBP "Victoria de Girón". In chronic reservoirs no undesirable response has been obtained. Farmacokynetics modifies itself in them in terms of Gamma globulin consumption, this not happening in immunes. [ABSTRACT FROM AUTHOR]

Introduction: The use of various diagnostic techniques is increasingly common in pandemic scenarios. It is important to update evaluations of their metric properties in different times and settings., Objective: Evaluate metric properties of a SARS-CoV-2 rapid antigen test relative to a reference standard., Methods: We carried out a prospective evaluation study of the SARS-CoV-2 rapid antigen test as compared to the RT-PCR test, which is considered the reference standard. Our sample was comprised of 778 individuals, and we calculated sensitiv- ity, specificity, predictive values, prevalence and validity indices., Results: Of the total 778 samples, 70 were true positives, 658 were true negatives, and 27 were false negatives when compared to RT-PCR test results. We obtained a sensitivity of 75.3% (95% CI = 65.96-84.50); a specificity of 96.1% (95% CI = 94.53-97.59); 72.2% for positive predictive value, and 96.6% for negative predictive value. The estimated preva- lence was 11.9% and the validity index was 93.6%., Conclusions: The index values validate use of the SARS- CoV-2 rapid antigen test until prevalence falls below 2.5%, since as SARS-CoV-2 infection prevalence decreases, so does the predictive value of the PCR result. The use of the SARS-CoV-2 rapid antigen test on the Isle of Youth, Cuba, was decisive in the pandemic's clinical- epidemiological management.

The aetiology of diarrhoea in a patient in Cuba with HIV was investigated. Although molecular diagnostics are still not used in many under-resourced settings, here traditional methods were supported by use of PCR. This approach enabled detection of a dual infection (Cystoisospora belli and Enterocytozoon bieneusi), the latter of which was not identified by microscopy with Didier's trichromic staining., (Copyright © 2021 The Author(s). Published by Elsevier B.V. All rights reserved.)

Microscopy is the gold standard for diagnosis of intestinal parasitic diseases in many countries, including Cuba, although molecular approaches often have higher sensitivity as well as other advantages. Fecal samples from 133 patients were analyzed by light microscopy and also real-time multiplex qPCR targeting Giardia duodenalis, Cryptosporidium spp., and Entamoeba histolytica, and, separately, Dientamoeba fragilis. Microscopy revealed G. duodenalis occurred most commonly (17 patients), followed by Blastocystis spp. (12 patients). In a few patients, Entamoeba histolytica/E. dispar, Cryptosporidium spp., and Cyclospora cayetanensis were identified. Molecular analysis identified 4 more G. duodenalis infections and 2 more Cryptosporidium spp. infections; concordance between microscopy and PCR showed almost perfect agreement for G. duodenalis (κ = 0.88) and substantial agreement for Cryptosporidium (κ = 0.74). PCR indicated that E. dispar, rather than E. histolytica, had been identified by microscopy. Additionally, 16 D. fragilis infections were detected using molecular methods. Although both microscopy and molecular techniques have a place in parasitology diagnostics, for parasites such as D. fragilis, where microscopy can underestimate occurrence, molecular techniques may be preferable, and also essential for distinguishing between morphologically similar microorganisms such as E. histolytica and E. dispar. Although in resource-constrained countries such as Cuba, microscopy is extremely important as a diagnostic tool for intestinal parasites, inclusion of molecular techniques could be invaluable for selected protozoa., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)

Objectives: This study aimed to determine the allelic profiles of Treponema pallidum in patients confirmed with syphilis in Cuba (2018-2019) and to explore mutations leading to macrolide and tetracycline resistance., Methods: Multilocus sequence typing and polymerase chain reaction of rrn loci (23S and 16S rDNA), followed by Sanger sequencing, were used to define the allelic profile of TPA and resistance mutations, respectively., Results: Allelic profile 1.3.1 and the recombinant profile were identified, with 15.7.3 having an increased frequency. We did not detect the presence of the T. pallidum subspecies endemicum among syphilis patients, as in previous reports. A high frequency of macrolide-resistant strains and the absence of mutations potentially causing tetracycline resistance were found., Conclusions: Understanding the current status of treponemal infection in Cuban patients provides insights into the syphilis epidemiology.

Leptospirosis is a neglected disease causing severe infections in humans and animals. Due in part to misdiagnosis, this infectious disease results in nearly 60,000 deaths per year around the globe. This study represents the first effort to describe the diversity of pathogenic Leptospira in Cuba based on whole-genome sequencing. We have collected nineteen whole-blood samples from patients that were diagnosed as having leptospirosis between 2008 and 2012 in Cuba. In addition, we have enhanced our sample set by three historical strains that were used for the development of a human vaccine in 1990s. The Leptospira strains were grown and serotyped by the microscopic agglutination test, and the draft genomes were generated by NGS (Illumina). Subsequently, the core genomes were analyzed and compared to the genetic data available from other Caribbean islands and countries in Central America. Core genome Multi-locus Sequence Typing (cgMLST) revealed four different core genome clonal groups (cgCGs), with the highest number of samples belonging to L. interrogans, followed by L. borgpetersenii and L. kirschneri. All cgCGs that were found in Cuba have been also identified from multiple origins across the globe, except in neighbor countries and Central America. Serotyping divided the samples into the serogroups Canicola, Ballum and Pomona. The most frequent cgCGs, cgCG28, associated with serogroup Canicola, and cgCG15, associated with serogroup Ballum, have also been identified from samples isolated from dogs, rodents, and pigs; suggesting that these hosts represent the major source of human infection in Cuba. The vaccine strains did not significantly differ from the recent patient isolates. However, the increasing prevalence of samples belonging to the serogroup Ballum combined with the fact that the available vaccine in Cuba represents inactivated Leptospira belonging to serogroups other than Ballum, should be a valuable information for the National and Regional Leptospirosis Control Programs., Competing Interests: There are no competing interests. ADMED Microbiologie does not alter our adherence to PLOS ONE policies on sharing data and materials.

Background: The increased prevalence of syphilis in Cuba prompted us to map the circulating Treponema pallidum subsp. pallidum allelic profiles in this geographic region., Methods: Samples were collected from 2012 to 2017, from 83 male patients with ulcers or skin lesions, and were examined using multilocus sequence typing. Additionally, we analyzed the 23S rDNA and 16S rDNA regions for the presence of possible mutations leading to macrolide and tetracycline resistance., Results: Among 94% of fully typed strains, we found 7 different allelic profiles, of which 4 had not been previously described. More than 87% of patients were infected with the T. pallidum SS14-like group and only 8.2% with T. pallidum Nichols-like group. As in other countries, the 1.3.1 allelic profile (ie, SS14-like) was the most common. In addition, 1 of the newly described allelic profiles represents T. pallidum strains that arose by recombination events between members of different T. pallidum subgroups. More than 90% of patients were infected with treponemes harboring the A2058G mutation. However, we found no potential tetracycline-resistant T. pallidum mutations., Conclusions: Our results suggest that, in Cuba, tetracycline antibiotics could be used to treat syphilis in penicillin-allergic patients instead of macrolides., (© The Author(s) 2018. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Objectives: Bejel, caused by Treponema pallidum subsp. endemicum (TEN), was until now considered as a non-venereal disease endemic in areas with hot and dry climates. This study has identified TEN in clinical samples from Cuban patients previously diagnosed with syphilis., Methods: We performed sequencing-based molecular typing on 92 samples from Cuban individuals diagnosed with syphilis. Moreover, to differentiate T. pallidum subspecies, multi-locus sequence analysis (MLSA) was designed and was applied to suspicious samples., Results: Nine samples, from six patients, had a nucleotide sequence similarity (at all typing loci) to the Bosnia A genome, which is the infectious agent of bejel. Additionally, MLSA clearly supported a TEN classification for the treponemal samples. Clinical and epidemiological data from the six patients also suggested sexual transmission of bejel as well as the endemicity of this rare treponematosis in Cuba., Conclusions: Molecular identification of Treponema pallidum subsp. endemicum, the agent of bejel, in Cuban patients diagnosed with syphilis indicates the clear limitations of a diagnosis based exclusively on serology, geographical occurrence, clinical symptoms and anamnestic data. This finding has important implications for Global Public Health Systems, including paradigm changes regarding the location of endemic outbreaks, clinical aspects and transmission of this neglected disease., (Copyright © 2018 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Background: Sexually transmitted diseases (STDs) and in particular genital ulcer disease (GUD) have a major impact on morbidity and mortality in developing countries. The World Health Organization recommends the use of syndromic guidelines for the treatment of sexually transmitted infections (STIs) in resource-constrained countries. Surveillance of autochthonous etiologies provides epidemiological information contributing to the prevention and treatment of STIs. We investigated the etiology and factors associated with GUD among male patients attending a STD clinic in Havana, Cuba., Methods: Swabs from genital ulcers of 113 male patients, collected from May 2012 to June 2015, were analyzed using PCR for herpes simplex virus types 1 and 2, Treponema pallidum, Haemophilus ducreyi, and Chlamydia trachomatis. We also investigated the clinical and epidemiological characteristics associated with the presence of these pathogens in GUD., Results: At least one of the pathogens was detected in 70% of patients. The occurrence of the pathogens was herpes simplex virus type 2 (HSV-2) (51.3%), T. pallidum (29.2%), and C. trachomatis (1.8%). Co-infections occurred as follows: T. pallidum-HSV-2 (10.6%), C. trachomatis-HSV-2 (0.9%) and C. trachomatis-T. pallidum (0.9%). Herpes simplex virus type 1 and H. ducreyi were not detected. Ages 15 to 40 years, HIV-positive serostatus, and no condom use were significant risk factors for the presence of HSV-2 in genital ulcers., Conclusions: Our preliminary results highlight the predominance of HSV-2 and T. pallidum as the leading GUD etiologies in the study population and identified risk factors associated with HSV-2. This information should help to inform guidelines for better management of GUD in Havana, Cuba.

Coxiella burnetii is the causative agent of Q fever. In order to explore the occurrence of C. burnetii in ticks, samples were collected from horses, dogs and humans living in a Cuban occidental community. The species most commonly recovered were Amblyomma mixtum (67%), Rhipicephalus sanguineus s.l. (27%) and Dermacentor nitens (6%). Specific IS1111 PCR and amplicon sequencing allowed the identification of C. burnetii DNA in A. mixtum collected from a domestic horse. These findings, for first time in Cuba, indicate the need for an in-depth assessment of the C. burnetii occurrence in hosts and humans at risk of infection., (Copyright © 2015 Elsevier GmbH. All rights reserved.)

Unlabelled: Lyme disease has not been officially reported in Cuba. However, clinical cases have been serologically reported. Seroprevalence survey of Borrelia burgdorferi sensu stricto antibodies in humans in the country has not been conducted., Objective: To estimate the prevalence of borrelial antibodies in inhabitants of a village with historically high level of tick infestation., Methods: Serum specimens from 247 persons randomly selected from the population of the village were examined by IgG Western blot using B31 strain for estimating the prevalence of antibodies profile., Results: A seroprevalence value interval (95% CI) of 0.6%-7.2% was estimated for the studied population. The prevalent borrelial protein bands on immunoblots were 41, 72, 90/93, 34, 47, 60, 58, 56, 65/66 and 31 kDa in a decreasing order of significance., Conclusion: These results support the previous serological findings, suggesting the presence of this borreliosis in Cuba.

By using the monoclonal antibodies methodology we have classified Cuban serovars of leptospires isolated from blood culture of confirmed leptospirosis patients. The serogroups Pomona and Canicola were the most predominant found in our study. Pomona, Mozdok and Canicola serovars were the most prevalent types in these serogroups. Our study has essentially presented a validation of a monoclonal antibody method for the serotyping of Cuban leptospire isolates.

For the first time in Cuba the rapid serologic technologies available worldwide were evaluated for the screening and confirmation of human leptospirosis. As its clinical recognition is difficult, the fast etiological diagnosis is of vital importance. Sensitivity and specificity values higher than 90 % were obtained in the confirmatory systems, and of 85 % in the screening systems. Of the severe patients studied by these technologies 50 % were positive. 203 cases corresponding to 4 epidemic outbreaks were confirmed, as well as 12 sick persons vaccinated with vaxSPIRAL, which demonstrates the vaccine effectiveness (78.1%). We developed and applied a latex system for a rapid screening of leptospirosis (LeptoCuba), with an excellent sensitivity, specificity, reproducibility, and stability. The application of new technologies for the screening and fast confirmation of the disease allowed to increase the positivity and quality of the diagnosis from 2000 to 2006, strengthening the microbiological surveillance in the country.

A quantitative ELISA for the detection of IgG antibodies in response to the Cuban vaccine against the human leptospirosis (vax-SPIRAL) was applied to 930 volunteers'sera, 483 immunized with vax-SPIRAL and 447 with a vaccine against hepatitis B. Samples were taken before beginning the study, 21 days after the second dose and a year later. A high seroprevalence of antibodies to the vaccine serovars was observed before beginning the study. The initial value of the response doubled at 21 days of the second dose in 45 % of the individuals. There were markedly significant differences (p=0,000000) between both groups. A similar response to the three leptospiral serovars was found. After the year the levels of antibodies decreased; however, 23.1% of the individuals were able to duplicate their level of antibodies regarding the initial moment, and the significant difference with the group that received the vaccine against hepatitis B still existed. The application of this Cuban immunogen amomg the main risk groups was recommended.

Objectives: To assess the sensitivity, specificity, reproducibility, and stability of five latex agglutination systems for detecting antibodies against leptospira in human and animal sera, by using the Leptospira serotypes that are most widely prevalent in Cuba., Methods: We performed an analytic and descriptive study with 706 human sera (65 tested positive for antibodies against leptospira with microagglutination (MAT) and hemagglutination (HA) techniques; 156 sera that tested negative with MAT and HA); 485 sera from 424 patients who had clinical or epidemiologic signs of leptospirosis; and 29 animal sera (16 from equines, 6 from bovines, 5 from porcines, 1 from a canine, and 1 from an ovine). All of the samples were tested with five latex conjugates made from whole cells of Leptospira interrogans, specifically the four serogroups that circulated most widely in Cuba from 2002 to 2004. The cells obtained from cultured cell lines yielded four specific conjugates (latex-canicola, latex-icterohemorrhagiae, latexpomona, and latex-sejroe), as well as one latex conjugate made from a combination of all four serogroups in equal quantities (latex-pool). In addition, samples were tested with the commercial latex agglutination Lepto Tek Tri Dot (bioMeriuex, France) kit. The stability and reproducibility of the latex conjugates were assessed through monthly controls over a period of 6 months with positive and negative sera., Results: Of the systems that were assessed, the best combination of sensitivity and specificity was obtained with the latex-Pool conjugate (93,8% and 90,4%, respectively). The best combination of positive and negative predictive values was seen with the latex-Sejroe conjugate (90,9% and 95,8%), respectively), followed by the latex-Pool conjugate (94.2% and 96.6%, respectively). The positive and negative predictive values of the Lepto Tek Dri Dot commercial system were 78.5% and 88.4%, respectively. Among the 137 patient samples that tested positive for one of the serotypes when MAT was used, latex conjugates succeeded in correctly identifying 107 (78.1%), whereas the latex-Pool conjugate detected 116 (84.7%) positive sera. When animal sera were tested, the latex-Pool conjugate detected the greatest number of positive serum samples and showed the greatest concordance with MAT (93.1%). The conjugates studied showed good stability and reproducibility., Conclusions: Latex conjugates made from whole cells of the most widely circulating leptospira in Cuba showed a degree of concordance with MAT that was similar to or better than that seen with the Lepto Tek Dri Dot commercial system, both in human and animal sera. We recommend more widespread use of the latex-Pool conjugate in Cuba in the initial screening for antibodies against leptospira.

The seroconversion of 408 vaccinated individuals and 135 placebo included in 2 clinical trials of the Cuban vaccine against human leptospirosis was studied. 2 vaccine doses and 5 schemes were studied. Of 38 vaccinated subjects (Phase I), 11 (29 %) seroconverted by MAT and 12 (32 %) by ELISA, whereas in 33 placebo, seroconversion was observed in 2 (6 %) and 3 (9 %), respectively. In Phase II, of 68 vaccinated individuals (doses of 0.25 mL) and of 65 (doses of 0.50 mL), seroconversion was attained in 21 (31 %) and 16 (25 %) by ELISA, respectively, 9 by MAT (13 %) and 7 (11 %) were positive. There were no significant differences between the doses used. The seroconversion by MAT in 237 subjects vaccinated with different schemes was 22.4 %. No marked differences were observed between them. In most of the reactive individuals, antibody levels were found in at least one of the vaccine strains. It was recommended to search and evaluate other methods to show in vivo the level of protection of this vaccine.

Introduction: Vasculitis are characterised by the inflammatory infiltrate, chiefly of mononuclear cells, in the walls of the blood vessels, which can lead to occlusion with necrosis and the subsequent infarction of the affected tissue., Aims: The Objective of this study was to determine the clinical, anatomicopathological and neurophysiological aspects of vasculitic neuropathies in infancy., Patients and Methods: Each patient was submitted to the following tests: a complete hemogram, systemic lupus erythematosus cells (LE cells), lupus anticoagulant, antinuclear antibodies, neutrophil anticytoplasmic antibodies, venereal disease research laboratory test (VDRL), erythrocyte sedimentation rate, liver transaminases, serological testing for hepatitis C, B and A, cytochemical study of the cerebrospinal fluid, study of motor and sensory conduction, electromyography and nuclear magnetic resonance, when required; a biopsy of the sural nerve was performed, which was replaced by a necropsy if the patient died., Results: 15 patients from a total of 25 who were studied had vasculitic neuropathies; the most usual presentation was multiple mononeuropathy; aetiologies found included microscopic polyangiitis, systemic lupus erythematosus, JRA, overlap syndrome and several undetermined vasculitis. Of the patients who were submitted to a biopsy, 75% showed signs of vasculitis, which affected the small and medium sized vessels in 62.5% of patients., Conclusions: The presence of neuropathy in association with symptoms and signs of systemic involvement suggested the possibility of a neuropathy in the course of a vasculitis. The examination of biopsy specimens of the sural nerve is useful for the diagnosis and classification of the aetiology of vasculitis. Response to treatment with immunosuppressant drugs was good, both in the case of the neuropathy and of the underlying disease.

Objectives: To evaluate the efficacy of vax-SPIRAL, a Cuban vaccine against leptospirosis, and to provide additional information concerning the safety of this vaccine (which was developed by Cuba's Finlay Institute)., Methods: This phase III efficacy trial of vax-SPIRAL was controlled, randomized, and double blind. The control vaccine used for the trial was Heberbiovac-HB (Heber Biotec, Cuba), a recombinant hepatitis B vaccine. The randomization unit for allocating persons to the study group or the control group were 523 family physician offices in the selected municipalities. The study covered the entire population of males and females from 20 to 64 years old who voluntarily agreed to participate, from the municipalities of Ranchuelo, Quemado, Santo Domingo, Encrucijada, Corralillo, Cifuentes, and Camajuaní, which are in the province of Villa Clara, in the central region of Cuba. The vaccinations were given in the physicians' offices between February and July 1998, with an interval of 6 weeks between the two doses. The follow-up period was 12 months. A case was considered positive if a person who had received the two doses of the vaccine became ill with leptospirosis more than 21 days after receiving the second dose, with the diagnosis confirmed through serological and microbiological methods. We calculated the efficacy of the vaccine and the relative risk of becoming ill with leptospirosis after the vaccination. For the safety study, two persons were chosen at random from among the individuals vaccinated at the office of each physician participating in the study. Follow-up of local and systemic adverse reactions was carried out by the family physicians during the seven days after the application of each dose. The level of statistical significance was set at 0.05., Results: A total of 101 832 persons were vaccinated, with 50 354 of them (49.4%) receiving the leptospirosis vaccine and 51 478 of them (50.6%) receiving the control vaccine. The efficacy of the vax-SPIRAL vaccine was 78.1% (95% confidence interval (CI): 59.2% to 88.3%), and the relative risk of becoming ill with leptospirosis after receiving the leptospirosis vaccine was 0.22 (95% CI: 0.12 to 0.41). General discomfort was the most frequent systemic adverse reaction, and mild spontaneous pain at the injection site was the most frequent local effect. The local and systemic adverse reactions were both more frequent in the study group than in the control group (P = 0.003). There were no serious adverse events., Conclusion: The vax-SPIRAL vaccine proved to be safe and efficacious for leptospirosis control. The vaccine is recommended for use in preventing this disease among groups at risk of contracting it.

The non-treponemic fast detection test of plasmatic reagines (RPR) and the treponemic hemagglutination test of Treponema pallidum were used in the detection of infection due to T. pallidum in 60 males presenting HIV/AIDS infection with clinicoepidemiological diagnosis of syphilis. It was confirmed that 30% presented recently acquired symptomatic or latent syphilis and that 10% had markers of past treated infection or of late acquired latent syphilis, whereas in the other 60% no serological reactivity was detected. A seroprevalence study of reaginic antibodies was conducted by RPR in 59 HIV/AIDS females, using 67 women negative to this virus as controls. All of them had no symptoms compatible with the syphilitic infection. It was concluded that 20.3% and 11.9%, respectively, presented reactivity, which established a probable diagnosis of syphilis or a seroresistance to a previouos syphilis. These results showed a close association between syphilis and HIV/AIDS and that both diseases may coexist in a same patient.

A multidisciplinary group was created to confirm the existance of human leptospirosis in the province of Villa Clara where by the end of June, 1977, there was a considerable increase of febrile cases with symptoms and signs consistent with diseases such as hemorrhagic dengue and human leptospirosis. The National Laboratory of Reference of Leptospires from "Pedro Kouri" Institute, organized a set of direct and indirect diagnostic techniques as a working strategy that would serve to confirm this health problem. As a final result, it was observed that the Ballum, Pomona, Canicola and icterohaemorrhagiae serogroups showed the highest percentage of appearance among the studied cases. A total of 7 cases had active infection, since they were positives by the passive hemoagglutination method. The four severe cases studied by passive hemoagglutination and microagglutination were positive. Sera from the 3 patients with febrile syndrome of unknown ethiology were negative by these 2 techniques. The 3 samples obtained from the autopsy of a dead were positive by direct exam in dark field and staining of immunoperoxidase. The monosera of the dead subjects were highly reactive by passive hemagglutination (titers from 1-10 and up to 1-640). 2 hemocultures were typified as Ballum; 2 urines and 1 hemoculture were positive by polymerase chain reaction. In this way, a fast answer was given to the health public authorities from the Viceministry of Hygiene and Epidemiology of Cuba on confirming microbiologically the existance of the disease. lt was sugggested to administer the Cuban vax SPIRAL vaccine in the affected area.

Two possible cases of Lyme disease, which has not been reported in Cuba, but whose existence has been suspected for some years, are reported. These cases that were bitten by ticks and presented signs and symptoms compatible with this disease, according to literature, were serologically confirmed by different laboratory techniques (indirect immunofluorescence, ELISA and Western Blotting). The results suggest the presence of this borreliosis in Cuba.

It was analyzed the behavior of the resistance of 3 organophosphated insecticides (malathion, clorpirifos and methyl-pyrimifos), 3 pyrethroids (deltamethrin, lambda-cyhalothrin and cypermethrin), and 1 carbamate (propuxur) in populations of Culex quinquefasciatus from 2 municipalities of the province of Santiago de Cuba. The values of the resistance factor proved that there is resistance to malathion and clorpirifos. However, in spite of the existence of a high frequency of the mechanisms of elevated esterases and altered acetylcholinesterase no resistance to methylpymirifos, was observed which demonstrated that this insecticide is not affected by these mechanisms selected in our populations of Culex quinquefasciatus. There was resistence to deltamethrin, and lambda-cyhalothrin in Santiago de Cuba, whereas it was moderate to cypermethrin in Santiago and San Luis. Resistance to deltamethrin was also found in San Luis, but it was mild to lambda-cyhalothrin. The results obtained from the use of the synergists S,S,S tributyl phosphotritiade (DBF) and piperonyl butoxide (PB) indicated that the mechanisms of resistance of unspecific esterases and oxidases of multiple function are involved in the resistance to pyrethroids in both strains from Santiago de Cuba and San Luis. It was determined by the biochemical tests that there existed a high frequency of the mechanisms of esterases and altered acetylcholinesterase. The results of the polyacrylamide gel electrophoresis (PAGE) showed that esterase B1 appears more frequently associated with esterases A6 and B6. It was inferred that this association could be connected with the resistance to pyrethroids.

This study was carried out in 1991 to learn the behavior of enteropathogenic agents causing acute diarrheal diseases in Cuba. 30 children, admitted in hospitals or seen in outpatient services for acute diarrheal diseases, were selected in each province taking into account that they had not received antibiotic or chemotherapy treatments in the previous 72 hours. Feces samples were taken from all patients for virological, bacteriological, and parasitological studies, and results were sent to the Pedro Kourí Institute of Tropical Medicine. Data were processed in DBASE III. Higher positivity indices were attained in the winter months. The causative agents most frequently found were: rotavirus (8.2%); Entamoeba histolytica (6.1%); and Salmonella (4.2%). Escherichia coli, Campylobacter, Shigella and rotavirus showed higher indices in winter. Shigella flexneri and Shigella sonnei predominated. Salmonella serogroups D, B, and C, and enteropathogenic Escherichia coli 0119 and 026 subsets were the most frequently found.

Seven patients with acute promyelocytic leukemia (APL) were treated with all-trans retinoic acid (ATRA). Five (71.4%) achieved complete remission (CR). Most side effects were transient and well tolerated. Hyperleukocytosis was the major adverse effect. These observations confirm the efficacy of ATRA for inducing CR in APL.

A survey related to the detection of precancerous lesions of the oral cavity has been done in Cuba for the first time. The sample comprised 749 randomly selected workers from Havana City Province, taking into account the census records of the Cuban population up to 1979. Prevalence of lesions and their relation to age, sex and predisposing factors, such as smoking, alcohol habits and mechanical trauma were studied. 4.4% of leukoplakia and preleukoplakia considered together and 2.1% leukoplakia alone, and two cases of oral lichen planus and leukokeratosis nicotina palati (0.1% of each) were found. The former lesions were more frequently encountered in people above 50 years old, specially in males and specifically among those who had smoked for more than 10 years. Sites of location most frequently encountered were the buccal mucosa and the labial commissures.