Jaime Carmona-Fonseca

Objetivos. Identificar los genotipos de Plasmodium vivax en población gestante, y no gestante y explorar su asociación con mediadores inmunes. Materiales y métodos. Se siguieron durante 120 días dos cohortes de pacientes con malaria vivax no complicada en Puerto Libertador y Tierralta, Córdoba, Colombia: 41 gestantes y 46 no gestantes, todas tratadas con el tratamiento estándar. Se compararon los genotipos parasitarios (microsatélites Pv3.27, Pv3.502 y Pv1.501) y la expresión de mediadores inmunes del hospedero (IL-13, IL-10, TNF-alfa, IFN-gamma, IL-8, TGF-beta, Fox-P3, PD-L1) entre infecciones primarias y recurrentes. Resultados. La frecuencia de recurrencias fue mayor en gestantes (41,6%), que en no gestantes (8,7%). La diversidad genética parasitaria fue mayor en gestantes, aunque sinalelos exclusivos. Las recurrencias fueron genéticamente homólogas (mismos alelos) solo en 23% y 33% de los casos en gestante y no gestantes, respectivamente. En cuanto a los mediadores inmunes, solo la expresión de Fox-P3 varió significativamente en gestantes, con mayor expresión en el episodio primario que en el recurrente. Conclusiones. Las mujeres embarazadas están expuestas a una alta frecuencia de recurrencias de malaria vivax, con alta variación genética del parásito, lo que puede afectar el desarrollo de inmunidad protectora efectiva y favorecer desenlaces obstétricos adversos, tanto maternos como neonatales. Estos hallazgos plantean la necesidad de fortalecer y optimizar las acciones de prevención y tratamiento de la malaria vivax durante la gestación.

Background: The meanings and experiences related to malaria in pregnancy (MiP) and its processes of social determination of health (PSDH) have not been reported in the world scientific literature. The objective was to understand the meanings and experiences of MiP, and to explain their PSDH in an endemic area from Colombia, 2022. Methods: Critical ethnography with 46 pregnant women and 31 healthcare workers. In-depth and semi-structured interviews, focus group discussions, participant and non-participant observations, and field diaries were applied. A phenomenological-hermeneutic analysis, saturation and triangulation was carried out. The methodological rigor criteria were reflexivity, credibility, auditability, and transferability. Results: At the singular level, participants indicated different problems in antenatal care and malaria control programmes, pregnant women were lacking knowledge about MiP, and malaria care was restricted to cases with high obstetric risk. Three additional levels that explain the PSDH of MiP were identified: (i) limitations of malaria control policies, and health-system, geographic, cultural and economic barriers by MiP diagnosis and treatment; (ii) problems of public health programmes and antenatal care; (iii) structural problems such as monetary poverty, scarcity of resources for public health and inefficiency in their use, lacking community commitment to preventive actions, and breach of institutional responsibilities of health promoter entity, municipalities and health services provider institutions. Conclusion: Initiatives for MiP control are concentrated at the singular level, PDSH identified in this research show the need to broaden the field of action, increase health resources, and improve public health programmes and antenatal care. It is also necessary to impact the reciprocal relationships of MiP with economic and cultural dimensions, although these aspects are increasingly diminished with the predominance and naturalization of neoliberal logic in health.

This study compared the clinical–parasitological profiles of gestational (GM), placental (PM), and congenital (CM) malaria in northwestern Colombia. A cross-sectional study with 829 pregnant women, 549 placentas, and 547 newborns was conducted. The frequency of GM was 35.8%, PM 20.9%, and CM 8.5%. P. vivax predominated in GM; in PM, the proportion of P. vivax and P. falciparum was similar; in CM, P. falciparum predominated. The main clinical findings were headache (49%), anemia (32%), fever (24%), and musculoskeletal pain (13%). The clinical manifestations were statistically higher in P. vivax infections. In submicroscopic GM (positive with qPCR and negative with thick blood smear), the frequency of anemia, sore throat, and a headache was statistically higher compared with pregnant women without malaria. GM, PM, and CM reduce birth weight and head circumference. In Colombia, this is the first research on the clinical characteristics of GM, PM, and CM; contrary to evidence from other countries, P. vivax and submicroscopic infections are associated with clinical outcomes.

This study aimed to evaluate the accuracy of the thick blood smear (TBS) versus quantitative polymerase chain reaction (qPCR) for the diagnosis of malaria associated with pregnancy (MAP) caused by P. falciparum or P. vivax in Colombia in its gestational malaria (GM), placental malaria (PM), and congenital malaria (CM) forms as well as to compare its accuracy in different subgroups of pregnant women according to the presence of fever, anemia and a history of malaria. This was a diagnostic evaluation of 829 pregnant women, 579 placentas, 381 umbilical cord samples, and 221 neonatal peripheral blood samples. Accuracy was evaluated based on the parameters of sensitivity, specificity, predictive values, likelihood ratios, and validity index, with their 95% confidence intervals. The frequency of GM was 36% (n = 297/829), PM 27% (n = 159/579), and CM 16.5% (n = 63/381) in umbilical cord samples and 2% (n = 5/221) in neonatal peripheral blood samples. For GM, the sensitivity was 55%, with higher rates in those infected with P. vivax (68%), with a history of malaria (69%), and with fever (96%). These three subgroups presented the best results in terms of the negative likelihood ratio and validity index. For PM, sensitivity was 8%; in subgroup analyses in terms of species, symptomatology (anemia and fever), and history of malaria, it was 1–18%, and the negative likelihood ratio was >0.80 in all subgroups. No false positives were recorded in any of the subgroups. The TBS did not detect any cases of CM. This study found the TBS yielded satisfactory results in terms of diagnosing GM for P. vivax, pregnant women with previous malaria and febrile. It also showed that the TBS is not useful for diagnosing PM and CM. It is necessary to conduct surveillance of MAP with molecular methods in in groups where TBS is deficient (asymptomatic GM, P. falciparum, and pregnant women without history of malaria) to optimize the timely treatment of PM and CM, avoid the deleterious effects of MAP and achieve the malaria elimination goals in Colombia.

Passive immunity acquired through transplacental IgG transport is essential to protect infants against pathogens as childhood vaccination programs begins. Diarrhea caused by rotavirus and neonatal tetanus are common and potentially fatal childhood infections that can be prevented by transplacental IgG. However, it is not known whether maternal infections in pregnancy can reduce the transfer of these antibodies to the fetus. This study evaluated the effect of submicroscopic Plasmodium infection during pregnancy on the transfer of maternal IgG antibodies against rotavirus (anti-RV) and tetanus toxoid (anti-TT) to newborns of pregnant women residing in Puerto Libertador and Tierralta, Colombia. Expression of different immune mediators and levels of IgG against rotavirus and tetanus toxoid were quantified in pregnant women with and without Plasmodium infection during pregnancy. Submicroscopic infection at the time of delivery was associated with a cord-to-maternal ratio (CMR) > 1 for anti-RV and < 1 for anti-TT IgG, as well as with an increase in the expression of immune mediators of inflammation (IFN-γ), anti-inflammation (IL-10, TGF-β), and regulation (FoxP3, CTLA-4). When compared by species, these findings (CMR > 1 for anti-RV and < 1 for anti-TT IgG) were conserved in submicroscopic Plasmodium vivax infections at delivery. The impact of Plasmodium infections on neonatal susceptibility to other infections warrants further exploration.

Objetivos. Evaluar la exactitud de gota gruesa (GG) frente a la reacción en cadena de la polimerasa (PCR) cuantitativa para la malaria asociada al embarazo (MAE). Materiales y métodos. Se realizó una revisión sistemática de pruebas diagnósticas en nueve bases de datos. Se evaluó la calidad metodológica con QUADAS. Se estimó sensibilidad, especificidad, cociente de probabilidad positivo (CPP) y negativo (CPN), razón de odds diagnóstica (ORD) y área bajo la curva ROC. Se determinó la heterogeneidad con el estadístico Q de Der Simonian-Laird y la incertidumbre con el porcentaje de peso de cada estudio sobre el resultado global. Resultados. Se incluyeron diez estudios con 5691 gestantes, 1415 placentas y 84 neonatos. En los estudios con nPCR (PCR anidada) y qPCR (PCR cuantitativa) como estándar, los resultados de exactitud diagnóstica fueron estadísticamente similares, con sensibilidad muy baja (50 y 54%, respectivamente), alta especificidad (99% en ambos casos), alto CPP y deficiente CPN. Usando nPCR la OR diagnóstica fue 162 (IC95%=66-401) y el área bajo la curva ROC fue 95%, mientras que con qPCR fueron 231 (IC95%=27-1951) y 78%, respectivamente. Conclusiones. Mediante un protocolo exhaustivo se demostró el bajo desarrollo de investigaciones sobre la exactitud diagnóstica de la GG en MAE. Se demostró que la microscopía tiene un desempeño deficiente para el diagnóstico de infecciones asintomáticas o de baja parasitemia, lo que afianza la importancia de implementar otro tipo de técnicas en el seguimiento y control de las infecciones por malaria en las gestantes, con el fin de lograr el control y posible eliminación de la MAE.

Background: Knowledge of severe malaria (SM) or complicated malaria is insufficient in all its components. The least known type is the one associated with Plasmodium vivax, compared to that caused by P. falciparum. The aim of this study was to provide a general overview of epidemiological information about the burden of SM, obtained from the National Public Health Surveillance System (SIVIGILA) for the period 2007–2020 in Colombia. Methods: A descriptive, retrospective, and cross-sectional study of secondary information was performed via SIVIGILA. Results: There were 9881 SM cases among 1,060,950 total malaria cases in Colombia in 2007–2020: 9.31 SM cases per 1000 malaria cases. During this period, there were 7145 SM cases due to the following species: Plasmodium vivax, 57.6%; P. falciparum, 38.6%; severe mixed malaria, 3.2%; and P. malariae, 0.6%. The most compromised organ systems are the hematological system (54.9%), the liver (9.1%), the kidneys (4.2%), the lungs (1.9%) and the brain (1.6%). Conclusions: There has been a reduction in malaria incidence in Colombia in the last 10–15 years, but there has also been a strong increase in SM incidence. We suggest emphasizing the prevention of the onset of severe malaria, with the early and accurate diagnosis of plasmodial infection.

Knowledge about malaria associated with pregnancy is scarce in Latin America, and in Colombia, little is known about the magnitude of this infection. A systematic review was conducted to determine the prevalence of malaria associated with pregnancy (MAP) and each of its three forms: gestational (GM), placental (PM), and congenital (CM) tested using thick blood smear (TBS) and PCR. Also to compare the proportion of cases dueto Plasmodium falciparumandPlasmodium vivaxin Colombia from the year 2000–2020. We searched in Pubmed, Science Direct, EMBASE, EMCare, Cochrane Library, Scielo, Lilacs, Google Scholar, libraries, and repositories of Colombian universities, to obtain data on prevalence of GM, PM and CM with their respective testing method. We performed a meta-analysis with a random-effects model to obtain pooled prevalence of MAP and its three forms categorized by testing methods (TBS and PCR). We used data from 14 studies (out of 258 screened) contributing 7932, 2506 women for GM and PM respectively, also data on 1143 umbilical cord blood samples, and 899 peripheral blood of neonates. We found prevalence by TBS as, MAP 4.5% (95%CI = 2.9–6.9), GM 5.8% (95%CI = 3.8–8.7), PM 3.4% (95%CI = 1.7–6.7) and CM 1.3% (95%CI = 0.6–3.0). With PCR the prevalence was, MAP 14.4% (95%CI = 7.6–25.5), GM 16.7% (95%CI = 9.0–28.8), PM 11.0% (95%CI = 4.1–26.3) and CM 16.2% (95%CI = 8.2–29.5). The prevalence of submicroscopic infection was 8.5% (95%CI = 3.4–19.7) in GM, 10.1% (95%CI = 3.5–25.5) in PM and 22.0% (95%CI = 13.2–34.3) in CM. Infections byP.vivaxwas dominant overP.falciparumwhen tested with TBS, the PCR test gave similar proportions ofP.falciparumandP.vivax. This meta-analysis has demonstrated high prevalence of MAP in Colombia, and highlights the urgent need to increase attention of researchers, research funding institutions, government agencies, and health authorities to study and intervene MAP, that has currently been under investigated.

Objetivo: determinar la eficacia y seguridad de la monoterapia con cloroquina en gestantes colombianas con ataque agudo no complicado de malaria vivax (MGV). Materiales y métodos: estudio de cohorte prospectiva en pacientes gestantes que consultaron de manera espontánea entre 1 febrero de 2015 y 31 diciembre de 2017 a los puestos de malaria o de control prenatal en dos poblaciones de Colombia, en quienes se confirmó el diagnóstico de Plasmodium vivax mediante gota gruesa y qPCR (quantitative polymerase chain reaction). Se midieron variables sociodemográficas, falla terapéutica (FT) y eventos adversos serios a los 28 días y la frecuencia de recurrencia-recaída (RR) con seguimiento de 120 días. Se aplicó el protocolo de la OMS para evaluar la eficacia de monoterapia con cloroquina (m-CQ). Resultados: se captaron 47 gestantes; en el seguimiento de 28 días no hubo pérdidas y hubo 4,2 % (2/47) de FT. En el seguimiento de 45 mujeres entre los días 29 y 120 hubo 11 pérdidas (24,4 % = 11/45) y 13 RR con frecuencia que varió entre 29 y 53 % según el tipo de análisis. Conclusiones: la cloroquina conserva muy alta eficacia para curar el ataque agudo de malaria vivax en malaria gestacional (MG) en Colombia, y continúa siendo una buena opción para el tratamiento de la fase aguda. La frecuencia de RR es alta. Se requieren estudios que evalúen alternativas terapéuticas en la MG. Hay urgente necesidad de disponer de medicamentos o procedimientos que reduzcan ese altísimo riesgo.

Parasitic infections are an important cause of global morbidity and mortality and are highly prevalent in "underdeveloped" countries. The presence of parasitic infections is associated with modulation of the immune system and changes in the response to bacterial and viral vaccines. The objective of this review was to compile, summarize and analyze information about immunomodulation by parasitic infections and its effects on the immune response to vaccines. We also identified the parasites most associated with immunomodulation of vaccine responses and those vaccines most affected. In addition, articles evaluating the effect of chemoprophylaxis for malaria on the immune response against vaccines were considered. The most affected vaccines are Bacillus Calmette-Guérin and bacterial polysaccharide vaccines. Malaria is the infection most associated with decreased response to vaccines; however, there are discordant results. Chemoprophylaxis for malaria did not change the immune response to vaccination. While parasitic infections can alter the immune response to vaccination, it is important to clarify the discrepancies and establish the mechanisms.