Human Q Fever on the Guiana Shield and Brazil: Recent Findings and Remaining Questions.

PURPOSE OF REVIEW: In this review, we report on the state of knowledge about human Q fever in Brazil and on the Guiana Shield, an Amazonian region located in northeastern South America. There is a contrast between French Guiana, where the incidence of this disease is the highest in the world, and other countries where this disease is practically non-existent. RECENT FINDINGS: Recent findings are essentially in French Guiana where a unique strain MST17 has been identified; it is probably more virulent than those usually found with a particularly marked pulmonary tropism, a mysterious animal reservoir, a geographical distribution that raises questions. SUMMARY: Q fever is a bacterial zoonosis due to Coxiella burnetii that has been reported worldwide. On the Guiana Shield, a region mostly covered by Amazonian forest, which encompasses the Venezuelan State of Bolivar, Guyana, Suriname, French Guiana, and the Brazilian State of Amapá, the situation is very heterogeneous. While French Guiana is the region reporting the highest incidence of this disease in the world, with a single infecting clone (MST 117) and a unique epidemiological cycle, it has hardly ever been reported in other countries in the region. This absence of cases raises many questions and is probably due to massive under-diagnosis. Studies should estimate comprehensively the true burden of this disease in the region.

Fifty years of primary health care in the rainforest: temporal trends in morbidity and mortality in indigenous Amerindian populations of Suriname.

BACKGROUND: The Amazonian Amerindian populations living in the southern and southwestern hinterlands of Suriname (South America) have come into contact with western health care since approximately fifty years ago. In this study, secondary data were used to assess the impact of Medical Mission's fifty-year old primary health care program on the health status of these populations. METHODS: Using data from the primary health care facilities of Medical Mission for 1965-1970, 1973-1977, 1982-1985, and 1997-2014, temporal trends in incidence and mortality of respiratory tract infections, gastroenteritis, and malaria; population composition; birth and death rates; and polyclinic consultations in these communities have been assessed over the period between 1965 and 2014. RESULTS: In the period covered by this study, the incidence of respiratory tract infections and gastroenteritis declined by about 75% and 53%, respectively, while malaria incidence rose sharply from the 1980s through 2005 but subsequently declined to levels approximating elimination. Crude death rates dropped by about 70% while birth rates declined by about 50% in the 1980s and since then remained at this level. The population doubled in size and increased in all age groups, particularly in the age group of ≥59 years. The infant mortality rate declined by 50%. In addition, the average yearly number of polyclinic visits per person decreased 6- to 7-fold during this period. CONCLUSIONS: The significant reduction of the infectious disease burden; the doubling of the population size and the growth of the proportion of elderly individuals due to the declining death rates; the declining infant mortality rates to levels comparable to the national average as well as the decline in average numbers of polyclinic consultations per person, indicate that Medical Missions health service provision achieved its goal of improving the health and survival of the indigenous people by providing free, accessible and permanent medical services. Building upon this successful experience Medical Mission could be instrumental in addressing potential contemporary life-style related health threats.

Primaquine double dose for 7 days is inferior to single-dose treatment for 14 days in preventing Plasmodium vivax recurrent episodes in Suriname.

BACKGROUND: Recurrent episodes of Plasmodium vivax are caused by dormant liver stages of the parasite, which are not eradicated by choloroquine. Therefore, effective treatment also includes the use of primaquine (PQ). However, this secondary preventive therapy is often not effective, mostly due to poor adherence to the relatively long treatment course, justifying a comparative study of the efficacy of different durations of PQ treatment. MATERIALS AND METHODS: We included patients presenting with an acute and documented P. vivax infection from January 2006 to February 2008. All patients received chloroquine 25 mg/kg over a 3-day period. Subsequently, patients in group 7D received PQ 30 mg/day for 7 days, and patients in group 14D received standard PQ 15 mg/day for 14 days. All doses were given under supervision and patients were followed up for at least 6 months. The Kaplan-Meier method was used to estimate cumulative probability of recurrence up to 12 months after treatment initiation stratified by treatment group. Cox regression was used to assess possible determinants for recurrent parasitemia. RESULTS: Forty-seven of the 79 included patients (59.5%) were allocated to group 7D and 32 patients (40.5%) were allocated to group 14D. Recurrent parasitemia was detected in 31.9% of the cases in group 7D compared to 12.5% of the cases in group 14D (hazard ratio [HR] =3.36, 95% CI 1.11-10.16). Cumulative probability for recurrent parasitemia at 3, 6, and 12 months was 0.201 (95% CI 0.106-0.362), 0.312 (95% CI 0.190-0.485), and 0.424 (95% CI 0.274-0.615) for group 7D and 0.100 (95% CI 0.033-0.279), 0.100 (95% CI 0.033-0.279), and 0.138 (95% CI 0.054-0.327) for group 14D, respectively. When adjusted for possible confounders, differences in recurrent parasitemia remained significant between the two regimens in Cox regression analysis. CONCLUSION: More than 30% of the patients receiving shorter treatment course had recurrent parasitemia, suggesting that the standard dose of 15 mg/day PQ for 14 days is more efficacious than 30 mg for 7 days in preventing P. vivax recurrent episodes. Furthermore, we suggest that P. vivax treatment in Suriname should be changed to PQ 30 mg/day for 14 days, as per Center for Disease Control and Prevention recommendation, in light of a recurrence rate of over 10%, even in group 14D.

Yellow fever in a traveller returning from Suriname to the Netherlands, March 2017.

A Dutch traveller returning from Suriname in early March 2017, presented with fever and severe acute liver injury. Yellow fever was diagnosed by (q)RT-PCR and sequencing. During hospital stay, the patient's condition deteriorated and she developed hepatic encephalopathy requiring transfer to the intensive care. Although yellow fever has not been reported in the last four decades in Suriname, vaccination is recommended by the World Health Organization for visitors to this country.

Assessing parasite clearance during uncomplicated Plasmodium falciparum infection treated with artesunate monotherapy in Suriname.

BACKGROUND: Artemisinin resistance in Plasmodium falciparum is suspected when the day 3 parasitemia is >10% when treated with artemisinin-based combination therapy or if >10% of patients treated with artemisinin-based combination therapy or artesunate monotherapy harbored parasites with half-lives ≥5 hours. Hence, a single-arm prospective efficacy trial was conducted in Suriname for uncomplicated P. falciparum infection treated with artesunate-based monotherapy for 3 days assessing day 3 parasitemia, treatment outcome after 28 days, and parasite half-life. METHODS: The study was conducted in Paramaribo, the capital of Suriname, from July 2013 until July 2014. Patients with uncomplicated Plasmodium falciparum infection were included and received artesunate mono-therapy for three days. Day 3 parasitaemia, treatment outcome after 28 days and parasite half-life were determined. The latter was assessed with the parasite clearance estimator from the WorldWide Antimalarial Resistance Network (WWARN). RESULTS: Thirty-nine patients were included from July 2013 until July 2014. The day 3 parasitemia was 10%. Eight patients (20.5%) could be followed up until day 28 and showed adequate clinical and parasitological response. Parasite half-life could only be determined from ten data series (25.7%). The median parasite half-life was 5.16 hours, and seven of these data series had a half-life ≥5 hours, still comprising 17.9% of the total data series. CONCLUSION: The low follow-up rate and the limited analyzable data series preclude clear conclusions about the efficacy of artesunate monotherapy in Suriname and the parasite half-life, respectively. The emergence of at least 17.9% of data series with a parasite half-life ≥5 hours supports the possible presence of artemisinin resistance.

Evidence of an increased incidence of day 3 parasitaemia in Suriname: an indicator of the emerging resistance of Plasmodium falciparum to artemether

The emerging resistance to artemisinin derivatives that has been reported in South-East Asia led us to assess the efficacy of artemether-lumefantrine as the first line therapy for uncomplicated Plasmodium falciparum infections in Suriname. This drug assessment was performed according to the recommendations of the World Health Organization in 2011. The decreasing number of malaria cases in Suriname, which are currently limited to migrating populations and gold miners, precludes any conclusions on artemether efficacy because adequate numbers of patients with 28-day follow-up data are difficult to obtain. Therefore, a comparison of day 3 parasitaemia in a 2011 study and in a 2005/2006 study was used to detect the emergence of resistance to artemether. The prevalence of day 3 parasitaemia was assessed in a study in 2011 and was compared to that in a study in 2005/2006. The same protocol was used in both studies and artemether-lumefantrine was the study drug. Of 48 evaluable patients in 2011, 15 (31%) still had parasitaemia on day 3 compared to one (2%) out of 45 evaluable patients in 2005/2006. Overall, 11 evaluable patients in the 2011 study who were followed up until day 28 had negative slides and similar findings were obtained in all 38 evaluable patients in the 2005/2006 study. The significantly increased incidence of parasite persistence on day 3 may be an indication of emerging resistance to artemether.