Related Experiment Videos
Imported malaria treated in Melbourne, Australia: epidemiology and clinical features in 246 patients
P Robinson1, A W Jenney, M Tachado
1Victorian Infectious Diseases Reference Laboratory, North Melbourne, Victoria.
Background:
Imported malaria is increasing in nonendemic countries, including Australia. The objective of this study was to describe the epidemiology and clinical features of travelers with imported malaria presenting to a specialist infectious diseases hospital.
Methods:
A retrospective case series of 246 consecutively admitted inpatients with laboratory confirmed malaria. The main outcome measures were the proportion of patients infected with each malaria species, and relationship between species and country of birth, area of acquisition, adequacy of chemoprophylaxis, clinical features, laboratory investigations, and treatment.
Results:
Plasmodium vivax caused 182 (68.9%) episodes, Plasmodium falciparum caused 71 (26.9%), Plasmodium ovale caused 5 (1.9%), and Plasmodium malariae 1 (0.4%). Fifty-six percent of patients reported chemoprophylaxis use. People born in a country with endemic malaria (36.6%) were less likely to have used chemoprophylaxis. Malaria was most commonly acquired in Papua New Guinea and Southeast Asia. The median times to diagnosis after return to Australia for P. falciparum and P. vivax infections were 1 and 9 weeks respectively. The longest interval between last arrival in Australia and presentation with P. falciparum malaria was 32 weeks. Fever (96%), headache (74%), and a tender or palpable spleen (40%), were the most common clinical features. Diarrhea was more common in P. falciparum, and rigors in P. vivax infections. Thrombocytopenia (71%), abnormal liver function tests and an elevated C-reactive protein (85%) were common. Six patients had severe falciparum malaria but no deaths occurred during the study period.
Conclusion:
Malaria remains a health threat for those traveling in endemic areas and is associated with failure to use chemoprophylaxis appropriately. Nonspecific clinical features may lead to delayed diagnosis and misdiagnosis. Malaria should be suspected in the febrile traveler, regardless of birthplace, prophylaxis, symptomatology, or the time that has elapsed since leaving the malarious area.
Insights
Imported malaria cases are rising in Australia, with Plasmodium vivax being the most common species. Delayed diagnosis is a risk due to non-specific symptoms, emphasizing the need to suspect malaria in febrile travelers.
Area of Science:
- Infectious Diseases
- Tropical Medicine
- Public Health
Background:
- Imported malaria incidence is increasing in non-endemic countries like Australia.
- Travelers returning from endemic regions pose a growing public health concern.
Purpose of the Study:
- To delineate the epidemiology and clinical characteristics of imported malaria cases in Australia.
- To identify factors contributing to delayed diagnosis and treatment of malaria in travelers.
Main Methods:
- Retrospective case series analysis of 246 laboratory-confirmed malaria inpatients.
- Examined malaria species, country of birth, acquisition location, chemoprophylaxis use, clinical signs, lab results, and treatment outcomes.
Main Results:
- Plasmodium vivax (68.9%) and Plasmodium falciparum (26.9%) were the predominant malaria species.
- Inadequate chemoprophylaxis use was noted, particularly in individuals born in malaria-endemic areas.
- Common symptoms included fever (96%) and headache (74%), with diagnosis delays up to 32 weeks for P. falciparum.
Conclusions:
- Malaria poses a significant risk to travelers, often linked to improper chemoprophylaxis.
- Non-specific symptoms can lead to delayed or incorrect malaria diagnoses.
- Clinicians should maintain a high index of suspicion for malaria in any febrile traveler, irrespective of their travel history or prophylaxis use.