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Background: Available information on the causes of death among people living with human immunodeficiency virus (PLHIV) in low- and middle-income countries (LMICs) remains scarce. We aimed to provide data on causes of death in PLHIV from two LMICs, Brazil and Mozambique, to assess the impact of clinical misdiagnosis on mortality rates and to evaluate the accuracy of minimally invasive tissue sampling (MITS) in determining the cause of death in PLHIV., Methods: We performed coupled MITS and complete autopsy on 164 deceased PLHIV (18 children, 36 maternal deaths, and 110 adults). HIV antibody levels and HIV RNA viral loads were determined from postmortem serum samples., Results: Tuberculosis (22.7%), toxoplasmosis (13.9%), bacterial infections (13.9%), and cryptococcosis (10.9%) were the leading causes of death in adults. In maternal deaths, tuberculosis (13.9%), bacterial infections (13.9%), cryptococcosis (11.1%), and cerebral malaria (8.3%) were the most frequent infections, whereas viral infections, particularly cytomegalovirus (38.9%), bacterial infections (27.8%), pneumocystosis (11.1%), and HIV-associated malignant neoplasms (11.1%) were the leading cause among children. Agreement between the MITS and the complete autopsy was 100% in children, 91% in adults, and 78% in maternal deaths. The MITS correctly identified the microorganism causing death in 89% of cases., Conclusions: Postmortem studies provide highly granular data on the causes of death in PLHIV. The inaccuracy of clinical diagnosis may play a significant role in the high mortality rates observed among PLHIV in LMICs. MITS might be helpful in monitoring the causes of death in PLHIV and in highlighting the gaps in the management of the infections., (© The Author(s) 2021. Published by Oxford University Press for the Infectious Diseases Society of America.)

Background: The effect of timing of exposure to first Plasmodium falciparum infections during early childhood on the induction of innate and adaptive cytokine responses and their contribution to the development of clinical malaria immunity is not well established., Methods: As part of a double-blind, randomized, placebo-controlled trial in Mozambique using monthly chemoprophylaxis with sulfadoxine-pyrimethamine plus artesunate to selectively control timing of malaria exposure during infancy, peripheral blood mononuclear cells collected from participants at age 2.5, 5.5, 10.5, 15, and 24 months were stimulated ex vivo with parasite schizont and erythrocyte lysates. Cytokine messenger RNA expressed in cell pellets and proteins secreted in supernatants were quantified by reverse-transcription quantitative polymerase chain reaction and multiplex flow cytometry, respectively. Children were followed up for clinical malaria from birth until 4 years of age., Results: Higher proinflammatory (interleukin [IL] 1, IL-6, tumor necrosis factor) and regulatory (IL-10) cytokine concentrations during the second year of life were associated with reduced incidence of clinical malaria up to 4 years of age, adjusting by chemoprophylaxis and prior malaria exposure. Significantly lower concentrations of antigen-specific T-helper 1 (IL-2, IL-12, interferon-γ) and T-helper 2 (IL-4, IL-5) cytokines by 2 years of age were measured in children undergoing chemoprophylaxis compared to children receiving placebo (P < .03)., Conclusions: Selective chemoprophylaxis altering early natural exposure to malaria blood stage antigens during infancy had a significant effect on T-helper lymphocyte cytokine production >1 year later. Importantly, a balanced proinflammatory and anti-inflammatory cytokine signature, probably by innate cells, around age 2 years was associated with protective clinical immunity during childhood., Clinical Trials Registration: NCT00231452., (© 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.)

Background: A main criterion to identify malaria vaccine candidates is the proof that acquired immunity against them is associated with protection from disease. The age of the studied individuals, heterogeneous malaria exposure, and assumption of the maintenance of a baseline immune response can confound these associations., Methods: Immunoglobulin G/immunoglobulin M (IgG/ IgM) levels were measured by Luminex® in Mozambican children monitored for clinical malaria from birth until 3 years of age, together with functional antibodies. Studied candidates were pre-erythrocytic and erythrocytic antigens, including EBAs/PfRhs, MSPs, DBLs, and novel antigens merely or not previously studied in malaria-exposed populations. Cox regression models were estimated at 9 and 24 months of age, accounting for heterogeneous malaria exposure or limiting follow-up according to the antibody's decay., Results: Associations of antibody responses with higher clinical malaria risk were avoided when accounting for heterogeneous malaria exposure or when limiting the follow-up time in the analyses. Associations with reduced risk of clinical malaria were found only at 24 months old, but not younger children, for IgG breadth and levels of IgG targeting EBA140III-V, CyRPA, DBL5ε and DBL3x, together with C1q-fixation activity by antibodies targeting MSP119., Conclusions: Malaria protection correlates were identified, only in children aged 24 months old when accounting for heterogeneous malaria exposure. These results highlight the relevance of considering age and malaria exposure, as well as the importance of not assuming the maintenance of a baseline immune response throughout the follow-up. Results may be misleading if these factors are not considered., (© The Author(s) 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Background: Invasive nontyphoidal Salmonella (iNTS) has emerged as a cause of bacteremia in African children and HIV-infected adults, which is associated with high mortality. Epidemiological data and burden of iNTS infections in resource-constrained settings are needed to better define preventive and curative strategies., Methods: Blood and, if appropriate, cerebrospinal fluid, were collected from children <15 years of age with fever or severe disease admitted to the Manhiça District Hospital and cultured for NTS; isolates were then characterized., Results: From January 2001 to December 2014, 41,668 of the 51,878 admitted children had a blood culture performed. Invasive NTS was isolated from 670 (1.6%) specimens collected from 41,668 patients; 69 (10.3% died). Salmonella enterica subspecies enterica serovar Typhi or Salmonella enterica subspecies enterica serovar Paratyphi A or C were only isolated in 14 (0.03%) patients. A total of 460 of 620 (74.2%) NTS isolates serotyped were Salmonella enterica subspecies enterica serovar Typhimurium (45% [116/258] of which were multilocus sequence type 313). The incidence of iNTS was 61.8 (95% confidence interval, 55.4-68.9) cases per 100,000 child-years, being highest among infants (217.7 cases/100,000 child-years). The incidence of iNTS declined significantly (P < .0001) over time, but the case fatality ratio remained constant at approximately 10%. Antimicrobial resistance of iNTS against most available antimicrobials has steadily increased, with a predominance of multidrug-resistant strains., Conclusions: The decreasing but still high incidence of iNTS, its high associated case fatality ratio, and the common detection of multidrug-resistant strains call for a need to improve treatment and prevention strategies for iNTS., (© The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Background: Acute bacterial meningitis (ABM) remains an important cause of mortality among African children. Epidemiologic data with regard to ABM infection are necessary for prioritizing public health interventions., Methods: We strengthened hospital-based surveillance of ABM among children admitted to Manhiça District Hospital (Maputo, Mozambique). Cerebrospinal fluid (CSF) samples were collected from children admitted to the hospital who met clinical criteria of ABM. Laboratory determinations were performed. Clinical information and outcome of cases were recorded., Results: During the first 12 months of surveillance, which began in January 2006, CSF samples were collected from 642 children <15 years of age with suspected meningitis (18% of all pediatric patients admitted to the hospital during that time). ABM was confirmed in 43 (7%) of the 642 cases. Haemophilus influenzae type b (Hib) (14 cases), pneumococcus (9 cases), and meningococcus (7 cases) represented approximately 70% of confirmed cases. Four of the 9 pneumococci were serotypes covered by the 7-valent pneumococcal conjugate vaccine. The case fatality rate among patients with ABM was 24% (8 of 33 with known outcome); an additional 8 patients left the hospital before discharge. The incidence of ABM was 85 per 100,000 population, which peaked at 2-12 months of age at 1078 cases per 100,000 population. All 9 pneumococci isolates were susceptible to chloramphenicol, and 8 were susceptible to penicillin (the additional 1 had intermediate resistance). For the 10 Hib isolates tested, only 1 was susceptible to chloramphenicol, and 5 were susceptible to ampicillin., Conclusion: These data reinforce the importance of ABM as a cause of hospital admission and death in rural sub-Saharan Africa. Most observed ABM cases could have been prevented by current pneumococcal and Hib conjugate vaccines.