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Serological data can provide estimates of human exposure to both malaria vector and parasite based on antibody responses. A multiplex bead-based assay was developed to simultaneously detect IgG to Anopheles albimanus salivary gland extract (SGE) and 23 Plasmodium falciparum antigens among 4185 participants enrolled in Artibonite department, Haiti in 2017. Logistic regression adjusted for participant- and site-level covariates and found children under 5 years and 6-15 years old had 3.7- and 5.4-fold increase in odds, respectively, of high anti-SGE IgG compared to participants >15 years. Seropositivity to P. falciparum CSP, Rh2_2030, and SEA-1 antigens was significantly associated with high IgG response against SGE, and participant enrolment at elevations under 200 m was associated with higher anti-SGE IgG levels. The ability to approximate population exposure to malaria vectors through SGE serology data is very dependent by age categories, and SGE antigens can be easily integrated into a multiplex serological assay., Competing Interests: Potential conflicts of interest. All authors: No reported conflicts of interest. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (Published by Oxford University Press on behalf of Infectious Diseases Society of America 2022. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

Background: Haiti is planning targeted interventions to accelerate progress toward malaria elimination. In the most affected department (Grande-Anse), a combined mass drug administration (MDA) and indoor residual spraying (IRS) campaign was launched in October 2018. This study assessed the intervention's effectiveness in reducing Plasmodium falciparum prevalence., Methods: An ecological quasi-experimental study was designed, using a pretest and posttest with a nonrandomized control group. Surveys were conducted in November 2017 in a panel of easy access groups (25 schools and 16 clinics) and were repeated 2-6 weeks after the campaign, in November 2018. Single-dose sulfadoxine-pyrimethamine and primaquine was used for MDA, and pirimiphos-methyl as insecticide for IRS., Results: A total of 10 006 participants were recruited. Fifty-two percent of the population in the intervention area reported having received MDA. Prevalence diminished between 2017 and 2018 in both areas, but the reduction was significantly larger in the intervention area (ratio of adjusted risk ratios, 0.32 [95% confidence interval, .104-.998])., Conclusions: Despite a moderate coverage, the campaign was effective in reducing P. falciparum prevalence immediately after 1 round. Targeted MDA plus IRS is useful in preelimination settings to rapidly decrease the parasite reservoir, an encouraging step to accelerate progress toward malaria elimination., (© The Author(s) 2021. Published by Oxford University Press for the Infectious Diseases Society of America.)

Background: Streptococcus pneumoniae, or pneumococcus, is a leading cause of morbidity and mortality in children worldwide. Pneumococcal conjugate vaccines (PCV) reduce carriage in the nasopharynx, preventing disease. We conducted a pneumococcal carriage study to estimate the prevalence of pneumococcal colonization, identify risk factors for colonization, and describe antimicrobial susceptibility patterns among pneumococci colonizing young children in Port-au-Prince, Haiti, before introduction of 13-valent PCV (PCV13)., Methods: We conducted a cross-sectional study of children aged 6-24 months at an immunization clinic in Port-au-Prince between September 2015 and January 2016. Consenting parents were interviewed about factors associated with pneumococcal carriage; nasopharyngeal swabs were collected from each child and cultured for pneumococcus after broth enrichment. Pneumococcal isolates were serotyped and underwent antimicrobial susceptibility testing. We compared frequency of demographic, clinical, and environmental factors among pneumococcus-colonized children (carriers) to those who were not colonized (noncarriers) using unadjusted bivariate analysis and multivariate logistic regression., Results: Pneumococcus was isolated from 308 of the 685 (45.0%) children enrolled. Overall, 157 isolates (50.8%) were PCV13 vaccine-type serotypes; most common were 6A (13.3%), 19F (12.6%), 6B (9.7%), and 23F (6.1%). Vaccine-type isolates were significantly more likely to be nonsusceptible to ≥1 antimicrobial (63.1% vs 45.4%, P = .002). On bivariate analysis, carriers were significantly more likely than noncarriers to live in a household without electricity or running water, to share a bedroom with ≥3 people, to have a mother or father who did not complete secondary education, and to have respiratory symptoms in the 24 hours before enrollment (P < .05 for all comparisons). On multivariable analysis, completion of the pentavalent vaccination series (targeting diphtheria, pertussis, tetanus, hepatitis B, and Haemophilus influenzae type b) remained significantly more common among noncarriers., Conclusions: Nearly a quarter of healthy children surveyed in Haiti were colonized with vaccine-type pneumococcal serotypes. This baseline carriage study will enable estimation of vaccine impact following nationwide introduction of PCV13., (Published by Oxford University Press for the Infectious Diseases Society of America 2021.)

Accurate malaria diagnosis is foundational for control and elimination, and Haiti relies on histidine-rich protein 2 (HRP2)-based rapid diagnostic tests (RDTs) identifying Plasmodium falciparum in clinical and community settings. In 2017, 1 household and 2 easy-access group surveys tested all participants (N = 32 506) by conventional and high-sensitivity RDTs. A subset of blood samples (n = 1154) was laboratory tested for HRP2 by bead-based immunoassay and for P. falciparum 18S rDNA by photo-induced electron transfer polymerase chain reaction. Both RDT types detected low concentrations of HRP2 with sensitivity estimates between 2.6 ng/mL and 14.6 ng/mL. Compared to the predicate HRP2 laboratory assay, RDT sensitivity ranged from 86.3% to 96.0% between tests and settings, and specificity from 90.0% to 99.6%. In the household survey, the high-sensitivity RDT provided a significantly higher number of positive tests, but this represented a very small proportion (<0.2%) of all participants. These data show that a high-sensitivity RDT may have limited utility in a malaria elimination setting like Haiti., (Published by Oxford University Press for the Infectious Diseases Society of America 2019.)

Background: Prior to introduction of rubella vaccine in Haiti's national immunization program, the Haitian government conducted a nationwide rubella-measles immunization campaign targeting persons 1-19 years of age to accelerate elimination of rubella and congenital rubella syndrome, while strengthening measles elimination. The national immunization campaign was conducted in phases by geographic region and combined multiple interventions to reach high coverage in all districts., Methods: We analyzed reported data on number of doses administered and results of rapid monitoring by "commune" (district) to evaluate coverage for each vaccine and intervention in target populations. We reviewed measles and rubella surveillance data from Haiti's national surveillance system., Results: Immunization registers recorded 4.7 million doses of measles-rubella (MR) vaccine administered to persons 1-19 years of age, reaching 80.2% of the estimated population of 1-4 year-olds and surpassing the target among 5-19 year-olds. In addition, 1 million children under 5 years of age received oral polio vaccine and vitamin A supplements, 1.5 million school children received deworming treatment nationwide, and over 500000 women 15-49 years old in 2 major population centers received diphtheria-tetanus vaccine. Based on administrative data, 102 (76.7%) of 133 communes attained 95% or greater coverage with MR vaccine among persons 1-19 years of age. Rapid monitoring in 118 communes indicated that coverage targets were reached in 52.5%. From 2007 to 2010, no confirmed cases of measles or rubella were reported from Haiti., Conclusions: The experience in Haiti suggests that rubella and congenital rubella syndrome can be eliminated through mass vaccination in countries with weak national immunization programs. However, high routine immunization coverage and improved surveillance are urgently needed to maintain measles and rubella elimination.

Background: A national campaign was conducted in Haiti in 2007-2008 to vaccinate all children and adolescents aged 1-19 years with measles-rubella vaccine in support of achieving the Region of the Americas' 2010 goal of eliminating rubella and congenital rubella syndrome (CRS). Measles-rubella vaccine was introduced into the country's routine childhood immunization schedule after the campaign., Methods: A nationwide, stratified, multistage cluster sample survey of 20859 children was conducted to assess coverage using house-to-house interviews., Results: Estimated national coverage with measles-rubella vaccine was 79.2% (95% confidence interval, 77.6%-80.7%), ranging from 90.2% in Nord-Ouest Department to 70.0% in Cite Soleil Metropolitan Area. National coverage was lower for children aged 1-5 years (76.7%) than for those aged 6-19 years (80.3%) (P< .001) but similar in rural departments (79.4%) and metropolitan areas (78.6%; P = .61). The reasons most frequently cited for nonparticipation in the campaign were that the child was ill or unavailable (18.6%), did not know vaccinations were important (13.8%), did not know when to go or forgot to go (13.3%), and did not have enough time (12.3%)., Conclusions: The measles-rubella vaccination campaign was critical for raising rubella immunity levels in children and adolescents in Haiti. To remain free of rubella transmission and CRS, Haiti must also achieve and sustain high routine measles-rubella vaccination coverage and maintain high-quality integrated measles-rubella and CRS surveillance, including laboratory-based confirmation for reported rash illnesses. If routine measles-rubella vaccination coverage is suboptimal or if gaps in coverage are identified, additional mass campaigns with measles-rubella vaccine will be necessary.

Background: Polymorphisms in CYP2B6 are known to predict increased steady-state plasma concentrations of efavirenz. We characterized relationships between genetic polymorphisms and plasma efavirenz concentrations among 45 Haitians who initiated antiretroviral therapy in Port-au-Prince., Methods: An observational study characterized relationships between clinical factors, pharmacokinetics, and treatment response among antiretroviral-naive patients initiating once-daily treatment with efavirenz plus twice-daily treatment with zidovudine and lamivudine. Plasma drug concentrations were determined at weeks 2 and 4. Drug doses were directly observed by field workers or designated family members. We retrospectively characterized relationships between efavirenz concentrations and 50 single-nucleotide polymorphisms in CYP2B6 and several polymorphisms in CYP2A6, CYP3A4, CYP3A5, and ABCB1., Results: Plasma specimens for efavirenz analysis were obtained from study participants a mean (+/- standard deviation) of 13.9 +/- 1.6 h after they received the dose. As expected, CYP2B6 516G-->T was associated with increased plasma efavirenz concentrations (Spearman rho = 0.71; P < .001), as were 10 polymorphisms in linkage disequilibrium with 516G-->T. Distinct CYP2B6 polymorphisms were associated with decreased plasma efavirenz concentrations (greatest absolute rho = 0.48; P = .001). Associations were replicated by results from a recent pharmacokinetic study involving 34 healthy, human immunodeficiency virus-negative African Americans., Conclusions: Relatively frequent CYP2B6 polymorphisms may predict decreased plasma efavirenz exposure in patients of African descent. If replicated in other cohorts, the implications of these novel associations for treatment response warrant further study.

Background: Data are limited about the effectiveness of pediatric antiretroviral therapy (ART) in low-income countries., Methods: We report the outcomes of consecutively treating 236 human immunodeficiency virus type 1 (HIV-1)-infected treatment-naive children with triple ART in Port-au-Prince, Haiti, between 1 May 2003 and 30 April 2006., Results: Kaplan-Meier survival analysis at follow-up demonstrated that 191 children (81%) remained in care, 21 (9%) were dead, and 24 (10%) were lost to follow-up. Independent baseline predictors of mortality were age <18 months, CD4(+) T cell percentage < or =5%, and weight-for-age Z score (WAZ) less than -3. Twelve months into ART, 56% of tested subjects had undetectable HIV-1 RNA loads. Median CD4(+) T cell percentages at 12 months increased by 15%, 11%, and 5% in children with baseline percentages of < or =5%, 6%-24%, and > or =25%, respectively (P<.01). The median WAZ at 12 months increased by 1.0, 0.6, and 0.2 in children with baseline WAZ less than -2, -2 to -1.1, and -1 or more, respectively (P<.01)., Conclusion: With continuous donor support, trained providers, and the availability of pediatric antiretroviral drug formulations, it proved feasible to deliver pediatric ART in Haiti. The effectiveness of this program should encourage efforts to make ART available for HIV-infected children in poor countries.

Twenty-one cases of acute flaccid paralysis (AFP) were reported on the island of Hispaniola in 2000. Laboratory analysis confirmed the presence of circulating vaccine-derived poliovirus (cVDPV) type 1 in stool samples obtained from patients. As a complement to the active search for cases of AFP, environmental sampling was conducted during November and December 2000, to test for cVDPV in sewage, streams, canals, and public latrines. Fifty-five environmental samples were obtained and analyzed for the presence of polioviruses by use of cell culture followed by neutralization and reverse-transcription polymerase chain reaction. Of the 23 positive samples, 10 tested positive for poliovirus type 1, 7 tested positive for poliovirus type 2, 5 tested positive for poliovirus type 3, and 1 tested positive for both poliovirus type 2 and type 3. By sequence analysis of the complete viral capsid gene 1 (VP1), a 2.1%-3.7% genetic sequence difference between 7 type 1 strains and Sabin type 1 vaccine strain was found. Phylogenetic analysis showed that these viruses are highly related to cVDPV isolated from clinical cases and form distinct subclusters related to geographic region. Our findings demonstrate a useful role for environmental surveillance of neurovirulent polioviruses in the overall polio eradication program.

On 8 March 2000 a case of laboratory-confirmed measles was detected in Haiti. Over the ensuing months, an explosive epidemic occurred that spread to 8 of the 9 departments of Haiti, including the nation's capital, Port au Prince. After peaking in the last half of November 2000, the epidemic began a rapid decline. The date of onset for the last confirmed case was 26 September 2001. During the 18 months of the epidemic, 1149 cases were confirmed. To control the epidemic, various strategies were employed, including vaccination campaigns that used fixed posts and door-to-door activities. Critical factors in the success of these campaigns were thorough training and supervision of field staff; a high-quality door-to-door vaccination strategy; multiple visits to homes; and monitoring of vaccine coverage by household during the course of the campaigns.

The mechanisms by which Cryptosporidium parvum cause persistent diarrhea and increased morbidity and mortality are poorly understood. Three groups of Haitian children <18 months old were studied: case patients, children with diarrhea not due to Cryptosporidium, and healthy control subjects. Compared with both control groups, children with acute cryptosporidiosis were more malnourished (including measures of stunting [P=.03] and general malnutrition [P=.01]), vitamin A deficient (P=.04), and less often breast-fed (P=.04). Markers of a proinflammatory immune response, interleukin (IL)-8 and tumor necrosis factor-alpha receptor I, were significantly elevated in the case population (P=.02 and P<.01, respectively), as was fecal lactoferrin (P=.01) and the T helper (Th)-2 cytokine IL-13 (P=.03). The counterregulatory cytokine IL-10 was exclusively elevated in the case population (P<.01). A Th1 cytokine response to infection was not detected. This triple cohort study demonstrates that malnourished children with acute cryptosporidiosis mount inflammatory, Th-2, and counterregulatory intestinal immune responses.

Women attending Haitian slum-based antenatal clinics were evaluated for sexually transmitted diseases (STDs): 110 (11%) of 996 were syphilis seroreactive, 313 (35%) of 903 had trichomoniasis, 110 (12%) of 897 had gonococcal or chlamydial cervical infection (or both), and 418 (47%) of 891 had at least one STD. Syphilis seroreactivity was associated with illiteracy (P = .007), lower socioeconomic status (P < .001), and a history of spontaneous abortion (P = .02). Of 663 evaluated sera, 56 (8%) had human immunodeficiency virus (HIV) antibodies. In multivariate analysis, positive HIV serostatus was associated with syphilis seroreactivity (P = .006), partner's unemployment (P = .002), and history of a previous sex partner (P = .04). Risk factors for gonococcal or chlamydial cervical infection were evaluated. Clinical assessment of cervical discharge, a World Health Organization algorithm, and a decision model based on local risk factors were 64%, 77%, and 89% sensitive, respectively, and 44%, 38%, and 43% specific, respectively, for predicting cervical infection. Alternative treatment approaches should be validated while waiting for affordable, simple, rapid, and accurate laboratory diagnostic tests for gonococcal and chlamydial cervical infections.

Mortality was evaluated in 1972 children who had received measles vaccines at 6-11 months of age that were 10-fold (medium titer) or 100-fold (high titer) greater than standard titer. Mortality among boys did not differ by vaccine titer and was similar to mortality in children who received standard-titer vaccine. Girl recipients of high-titer vaccine had somewhat greater mortality than girls who received medium-titer vaccine (risk ratio = 1.71, 95% confidence interval = 0.91-3.24). Increased mortality was associated with high-titer vaccine for girls but not for boys (P = .04). There was no evidence of selection bias or preferential health care by sex that might explain the differential mortality. This mortality pattern has been noted in two other populations with high background infant and childhood mortality. The biologic basis for this effect on mortality has not been determined. Data from this and other studies have resulted in discontinuation of the use of high-titer measles vaccines.

Antibodies to herpes simplex virus type 2 (HSV-2), antibodies to hepatitis B virus (HBV) core antigen (anti-HBc), and VDRL antibodies (serologic evidence of syphilis) were evaluated in women known to be infected with human immunodeficiency virus type 1 (HIV-1) (n = 95) or human T lymphotropic virus type I (HTLV-I) (n = 45) and controls (n = 89). HIV-1-seropositive women were more likely than controls to have antibodies to HSV-2 (88% vs. 54%; P less than .001), anti-HBc (67% vs. 43%; P = .008), and VDRL antibodies (21% vs. 8%; P = .02). Similarly, HTLV-I-seropositive women were more likely than controls to have antibodies to HSV-2 (82% vs. 54%; P = .003) and anti-HBc (67% vs. 43%; P = .008). There was no evidence that HIV-1 or HTLV-I predisposed to chronic hepatitis B virus infection. The stronger associations between HIV-1 and HTLV-I with HSV-2 than the associations with syphilis or HBV are consistent with the hypothesis that recurrent disruptions of mucous membranes caused by HSV-2 infections predispose to sexual transmission of HIV-1 and HTLV-I.