Strengthening surveillance, disease detection, and outbreak response through Guinea-Bissau's Frontline Field Epidemiology Training Program: a cross-sectional descriptive study.

Introduction: the goal of the Field Epidemiology Training Program (FETP) - Frontline is to strengthen the country's surveillance capacity at the district level to prepare and respond to health emergencies, including outbreaks, by training a skilled frontline public health workforce. We describe the FETP - Frontline program, including implementation, structure, achievements, impact, and its role in improving the epidemiological workforce capacity of Guinea-Bissau. Methods: this cross-sectional descriptive study uses 2015-2019 program data collected through record reviews and historical narratives from FETP students and graduates. We generated descriptive summary statistics using the Guinea-Bissau's FETP-Frontline program database, student assignments, and investigation reports, after reviewing the FETP standardized curriculum and program guidelines. Results: since its inception in 2016, FETP Frontline has implemented 14 cohorts and trained 198 frontline surveillance officers. Program participants improved surveillance data quality, investigated 51 outbreaks at national and regional levels, and contributed to disease research and surveillance in 227 separate field investigations. Participants frequently responded to priority health emergencies, including clusters or outbreaks of Zika, microencephalies, dengue, yellow fever, anthrax, malaria, and tuberculosis. Conclusion: Guinea-Bissau's FETP - Frontline program provides a practical example of an effective strategy to strengthen health systems through a well-prepared workforce trained to quickly detect and respond to health threats.

Adaptation to a Multiplex Bead Assay and Seroprevalence to Rift Valley Fever N Protein: Nampula Province, Mozambique, 2013-2014.

Rift Valley fever virus (RVFV) is endemic in sub-Saharan Africa (SSA), with outbreaks reported in the Arabian Peninsula and throughout SSA. The natural reservoir for RVFV are ruminants, with livestock populations exceeding 50% exposure rates in some areas of SSA. Transmission to humans can occur through exposure to infected livestock products or multiple species of mosquito vectors. In 2013 and 2014, cross-sectional surveys occurred in two districts of Nacala-a-Velha and Mecubúri in northern Mozambique, and participants provided blood samples for later serological assays. IgG against the N protein of RVFV was detected through multiplex bead assay (MBA). Of the 2,278 persons enrolled between the two surveys and study sites, 181 (7.9%, 95% confidence interval (CI): 6.9%-9.1%) were found to be IgG seropositive with increasing seroprevalence with older age and significantly higher seroprevalence in Nacala-a-Velha (10.5%, 8.8%-12.5%) versus Mecubúri (5.7%, 4.5%-7.1%). Seroprevalence estimates were not significantly different between the 2013 and 2014 surveys. Significant spatial clustering of IgG positive persons were consistent among surveys and within the two districts, pointing toward the consistency of serology data for making population-level assumptions regarding RVFV seroprevalence. A subset of persons (n = 539) provided samples for both the 2013 and 2014 surveys, and a low percentage (0.81%) of these were found to seroconvert between these two surveys. Including the RVFV N protein in an MBA antigen panel could assist elucidate RVFV exposure in SSA. IMPORTANCE Due to sporadic transmission, human contact with Rift Valley Fever Virus (RVFV) is difficult to ascertain at a population level. Detection of antibodies against RVFV antigens assist in estimating exposure as antibodies remain in the host long after the virus has been cleared. In this study, we show that antibodies against RVFV N protein can be detected from dried blood spot (DBS) samples being assayed by multiplex bead assay. DBS from two districts in northern Mozambique were tested for IgG against the N protein, and 7.9% of all enrolled persons were seropositive. Older persons, males, and persons residing closer to the coast had higher RVFV N protein seroprevalence. Spatial clustering of IgG positive persons was noted in both districts. These results show low exposure rates to RVFV in these two northern districts in Mozambique, and the ability to perform serology for the RVFV N protein from dried blood samples.

Multiplex serology for impact evaluation of bed net distribution on burden of lymphatic filariasis and four species of human malaria in northern Mozambique.

BACKGROUND: Universal coverage with long-lasting insecticidal nets (LLINs) is a primary control strategy against Plasmodium falciparum malaria. However, its impact on the three other main species of human malaria and lymphatic filariasis (LF), which share the same vectors in many co-endemic areas, is not as well characterized. The recent development of multiplex antibody detection provides the opportunity for simultaneous evaluation of the impact of control measures on the burden of multiple diseases. METHODOLOGY/PRINCIPAL FINDINGS: Two cross-sectional household surveys at baseline and one year after a LLIN distribution campaign were implemented in Mecubúri and Nacala-a-Velha Districts in Nampula Province, Mozambique. Both districts were known to be endemic for LF; both received mass drug administration (MDA) with antifilarial drugs during the evaluation period. Access to and use of LLINs was recorded, and household members were tested with P. falciparum rapid diagnostic tests (RDTs). Dried blood spots were collected and analyzed for presence of antibodies to three P. falciparum antigens, P. vivax MSP-119, P. ovale MSP-119, P. malariae MSP-119, and three LF antigens. Seroconversion rates were calculated and the association between LLIN use and post-campaign seropositivity was estimated using multivariate regression. The campaign covered 68% (95% CI: 58-77) of the population in Nacala-a-Velha and 46% (37-56) in Mecubúri. There was no statistically significant change in P. falciparum RDT positivity between the two surveys. Population seropositivity at baseline ranged from 31-81% for the P. falciparum antigens, 3-4% for P. vivax MSP-119, 41-43% for P. ovale MSP-119, 46-56% for P. malariae MSP-119, and 37-76% for the LF antigens. The seroconversion rate to the LF Bm33 antigen decreased significantly in both districts. The seroconversion rate to P. malariae MSP-119 and the LF Wb123 and Bm14 antigens each decreased significantly in one of the two districts. Community LLIN use was associated with a decreased risk of P. falciparum RDT positivity, P. falciparum LSA-1 seropositivity, and P. malariae MSP-119 seropositivity, but not LF antigen seropositivity. CONCLUSIONS/SIGNIFICANCE: The study area noted significant declines in LF seropositivity, but these were not associated with LLIN use. The MDA could have masked any impact of the LLINs on population LF seropositivity. The LLIN campaign did not reach adequately high coverage to decrease P. falciparum RDT positivity, the most common measure of P. falciparum burden. However, the significant decreases in the seroconversion rate to the P. malariae antigen, coupled with an association between community LLIN use and individual-level decreases in seropositivity to P. falciparum and P. malariae antigens show evidence of impact of the LLIN campaign and highlight the utility of using multiantigenic serological approaches for measuring intervention impact.

Clinical and Epidemiological Characterization of the First Recognized Outbreak of Dengue Virus-Type 2 in Mozambique, 2014.

Since the first reported epidemic of dengue in Pemba, the capital of Cabo Delgado province, in 1984-1985, no further cases have been reported in Mozambique. In March 2014, the Provincial Health Directorate of Cabo Delgado reported a suspected dengue outbreak in Pemba, associated with a recent increase in the frequency of patients with nonmalarial febrile illness. An investigation conducted between March and June detected a total of 193 clinically suspected dengue patients in Pemba and Nampula, the capital of neighboring Nampula Province. Dengue virus-type 2 (DENV-2) was detected by reverse transcriptase polymerase chain reaction in sera from three patients, and 97 others were classified as probable cases based on the presence of DENV nonstructural protein 1 antigen or anti-DENV immunoglobulin M antibody. Entomological investigations demonstrated the presence of Aedes aegypti mosquitos in both Pemba and Nampula cities.

Avaliação da cobertura, acesso, posse e uso da rede após a campanha de distribuição massiva nos distritos de Nacala - A - Velha e Mecuburi, Província de Nampula, 2013 / Evaluation of network coverage, access, ownership and use after the massive distribution campaign in Nacala - A - Velha and Mecuburi districts, Nampula Province, 2013

A malária é endémica em Moçambique e constitui um enorme problema de saúde pública. As redes mosquiteiras tratadas com insecticida de longa duração (REMILDs) são uma das medidas mais eficazes no controlo da malária, capazes de reduzir a incidência em cerca de 50% em áreas endémicas. Em 2013, decorreu campanha de distribuição universal de redes mosquiteiras na Província de Nampula. O estudo tinha como objectivo avaliar a cobertura, acesso, posse e uso da rede mosquiteira um mês após a campanha. Metodologia: Entre Setembro e Dezembro de 2013, foi realizado um estudo baseado no inquérito aos agregados familiares, um mês após a distribuição de REMILDs nos Distritos de Nacala-a-Velha e Mecubúri. Foram usados dados secundários para descrever a cobertura, acesso, posse e uso de redes mosquiteiras. Para a análise estatística, foram usadas tabelas 2x2 para calcular a razão dos produtos cruzados (OR) não ajustado e regressão logística para calcular OR ajustado. Para comparar as frequências nas duas populações foi usado o teste qui-quadrado e calculou-se o significado estatístico (valor-P). Resultado:Foram inquiridos 582 agregados familiares, dos quais 282 em Nacala-á-Velha e 300 em Mecubúri. No geral, agregados familiares inqueridos, que corresponde a 63.5% receberam pelo menos uma REMILD. A proporção de agregados familiares que receberam redes suficientes foi de 57.8% em Nacala-a-Velha e apenas 35.5% em Mecubúri. Conclusões e recomendações:A cobertura da campanha de distribuição de redes encontrada neste estudo foi baixa. Pretende-se realizar segunda fase do estudo um ano após a distribuição para medir o impacto da campanha

Malaria is endemic in Mozambique and is an enormous public health problem. Mosquito nets treated with long lasting insecticide (LLINs) are one of the most effective measures in malaria control, and can reduce the incidence by about 50% in endemic areas. In 2013 took place universal distribution campaign mosquito nets in Nampula province. The study aimed to evaluate the coverage, access, ownership and use of mosquito net one month after the campaign. Methods:In September and December 2013 a cross-sectional household survey took place two month after the distribution of LLINs in the districts of Nacala-a-Velha and Mecubúri. Were used secondary data to describe the coverage, access, ownership and use of mosquito nets. For the statistical analysis, 2x2 tables were used to calculate unadjusted odds ratios, and logistic regression was used to calculate adjusted odds ratios. Population frequencies were compared using the χ 2 test; and statistical significance was assessed by calculating p-values. Result:A total of 582 households were surveyed, of which 282 in Nacala-a-Velha and 300 in Mecubúri. Overall, 63.5% of surveyed households received at least one LLIN. The proportion of households that received enough nets, was 57.8% in Nacala-a-Velha and only 35.5% in Mecubúri. Conclusions:Despite being a campaign of universal distribution, the overall coverage of the distribution campaign was low. The second phase of the study will be conducted a year after the distribution to measure the campaign's impact.