Malaria and other febrile diseases among travellers: the experience of a reference centre located outside the Brazilian Amazon Region

Abstract

BackgroundMalaria is endemic in countries located in tropical and sub-tropical regions. The increasing flow of domestic and international travellers has made malaria a relevant health problem even in non-endemic regions. Malaria has been described as the main diagnosis among travellers presenting febrile diseases after returning from tropical countries. In Brazil, malaria transmission occurs mainly in the Amazon region. Outside this area, malaria transmission is of low magnitude.MethodsThis cross-sectional study aimed to describe the experience in the diagnosis of malaria in a reference centre located outside the Brazilian Amazon Region, emphasizing the differences in clinical and laboratory markers between cases of malaria and those of other febrile diseases (OFD). Medical charts from adult patients (≥18 years) who underwent a thick smear test (TST) for malaria, between January 2001 and December 2014, were retrospectively reviewed.ResultsA total of 458 cases referred to perform the TST were included. Malaria was diagnosed in 193 (42 %) episodes. The remaining 265 episodes (58 %) were grouped as OFD. The majority of malaria episodes were acquired in the Brazilian Amazon Region. The median time between the onset of symptoms and the TST was 7 days. Only 53 (11.5 %) episodes were tested within the first 48 h after symptom onset. Comparing malaria with OFD, jaundice, nausea, vomiting, and reports of fever were more prevalent in the malaria group. Low platelet count and elevated bilirubin levels were also related to the diagnosis of malaria.ConclusionsThe results indicate that outside the endemic area travellers presenting febrile disease suspected of being malaria underwent diagnostic test after considerable delay. The reporting of fever combined with a recent visit to an endemic area should promptly evoke the hypothesis of malaria. In these cases, specific diagnostic tests for malaria should be a priority. For cases that jump this step, the presence of elevated bilirubin or thrombocytopaenia should also indicate a diagnosis of malaria.

Does Malaria Cause Diarrhoea? A Systematic Review

“…or without a Plasmodium positive blood smears in the context of either HIV (33) or Typhoid (40) infections. Four studies included febrile patients who were either malaria positive or malaria negative by microscopy (32,38,51,62); in three of these studies the odds ratio of presenting with diarrhoea secondary to malaria was not significantly different from 1 whereas in one study the OR of 0.39 (95% CI 0.22, 0.68) was suggestive of a lower prevalence of diarrhoea in malaria cases compared to malaria uninfected patients ( Table 5). Taken together, these data suggest that diarrhoea is not more common among malaria patients than among patients attending hospital for other reasons.…”

Relapsing Fever Group Borreliae in Human-Biting Soft Ticks, Brazil

“…TBRF courses with febrile episodes and should be considered as a differential diagnosis within the spectrum of diseases that cause an undifferentiated febrile syndrome (UFS) ( 6 ). Although specific data are vague for the states where tick collections were performed in this study, UFS is common in Brazil; mosquitoborne viruses and malaria are the main etiologic agents ( 7 , 8 ). Nevertheless, febrile illnesses still remain underdiagnosed in a substantial proportion of the cases in the country ( 7 , 8 ).…”

“…Although specific data are vague for the states where tick collections were performed in this study, UFS is common in Brazil; mosquitoborne viruses and malaria are the main etiologic agents ( 7 , 8 ). Nevertheless, febrile illnesses still remain underdiagnosed in a substantial proportion of the cases in the country ( 7 , 8 ). The results of this study are a contribution to the knowledge of RFGB in human-biting Ornithodoros ticks, and stress the investigation of TBRF as a possible cause of UFS in Brazil.…”

Correction to: Malaria and other febrile diseases among travellers: the experience of a reference centre located outside the Brazilian Amazon Region

“…Following publication of the original article [1], one of the authors flagged that unfortunately their last name, Doltario, was incorrectly spelled as ‘Dotrario’. This has since been corrected in the original article [1].…”