Causes of non-malarial fever in Laos: a prospective study

Background Because of reductions in the incidence of Plasmodium falciparum malaria in Laos, identifi cation of the causes of fever in people without malaria, and discussion of the best empirical treatment options, are urgently needed. We aimed to identify the causes of non-malarial acute fever in patients in rural Laos. Methods For this prospective study, we recruited 1938 febrile patients, between May, 2008, and December, 2010, at Luang Namtha provincial hospital in northwest Laos (n=1390), and between September, 2008, and December, 2010, at Salavan provincial hospital in southern Laos (n=548). Eligible participants were aged 5–49 years with fever (≥38°C) lasting 8 days or less and were eligible for malaria testing by national guidelines. Findings With conservative defi nitions of cause, we assigned 799 (41%) patients a diagnosis. With exclusion of infl uenza, the top fi ve diagnoses when only one aetiological agent per patient was identifi ed were dengue (156 [8%] of 1927 patients), scrub typhus (122 [7%] of 1871), Japanese encephalitis virus (112 [6%] of 1924), leptospirosis (109 [6%] of 1934), and bacteraemia (43 [2%] of 1938). 115 (32%) of 358 patients at Luang Namtha hospital tested infl uenza PCR-positive between June and December, 2010, of which infl uenza B was the most frequently detected strain (n=121 [87%]). Disease frequency diff ered signifi cantly between the two sites: Japanese encephalitis virus infection (p=0·04), typhoid (p=0·006), and leptospirosis (p=0·001) were more common at Luang Namtha, whereas dengue and malaria were more common at Salavan (all p<0·0001). With use of evidence from southeast Asia when possible, we estimated that azithromycin, doxycycline, ceftriaxone, and ofl oxacin would have had signifi cant effi cacy for 258 (13%), 240 (12%), 154 (8%), and 41 (2%) of patients, respectively. Interpretation Our fi ndings suggest that a wide range of treatable or preventable pathogens are implicated in nonmalarial febrile illness in Laos. Empirical treatment with doxycycline for patients with undiff erentiated fever and negative rapid diagnostic tests for malaria and dengue could be an appropriate strategy for rural health workers in Laos. Funding Wellcome Trust, WHO–Western Pacifi c Region, Foundation for Innovative New Diagnostics, US Centers for Disease Control and Prevention

Factors associated with a measles outbreak in children admitted at Mahosot Hospital, Vientiane, Laos

<p>Abstract</p> <p>Background</p> <p>In 2002 and 2003 there were large outbreaks of measles in many provinces of Laos, including in Vientiane. We therefore conducted a study to determine risk factors associated with measles amongst children admitted at Mahosot Hospital, Vientiane.</p> <p>Methods</p> <p>A retrospective case-control study was conducted in 50 children with clinical measles who were matched by age and sex with 50 healthy children (who had never had a febrile rash) living in the same villages as the cases.</p> <p>Results</p> <p>The proportion of children with complete immunizations was significantly lower in the group with clinical measles compared to the controls [13/50 (26%) vs 34/50 (68%), <it>P </it>< 0.001). The percentage of children who had received measles vaccine at 9–23 months of age was significantly lower in the group with clinical measles compared to the healthy controls [12/50 (24%) vs 24/50 (48%), <it>P </it>= 0.01). The family educational and socio-economic status did not differ significantly (<it>P </it>> 0.05) between cases and controls.</p> <p>Conclusion</p> <p>These results emphasize the importance of intensification of measles immunization coverage in Laos. The strengthening of campaigns with large, widespread high second dose coverage is likely to be a key measure to prevent further measles outbreaks in Laos (192 words).</p

Reports of apparent mixed infections in Asia that included rickettsioses.

<p>Reports of apparent mixed infections in Asia that included rickettsioses.</p

Overview of PCR-based and DNA sequencing results.

*<p>positivity criteria in analogy to the Minimum Information for Publication of Quantitative Real-Time PCR Experiments (MIQE) <a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0002163#pntd.0002163-Bustin1" target="_blank">[19]</a>. GenBank accession numbers:</p>1<p>BankIt1587796 Seq2 KC283067.</p>2<p>BankIt1587796 Seq3 KC283068.</p>3<p>BankIt1587796 Seq1 KC283066.</p

Results of RDT stored at 35°C and in the hut in comparison to RDT stored at 4°C.

<p>Results of RDT stored at 35°C and in the hut in comparison to RDT stored at 4°C.</p

Causes of non-malarial fever in Laos: a prospective study

Background: Because of reductions in the incidence of Plasmodium falciparum malaria in Laos, identification of the causes of fever in people without malaria, and discussion of the best empirical treatment options, are urgently needed. We aimed to identify the causes of non-malarial acute fever in patients in rural Laos. Methods: For this prospective study, we recruited 1938 febrile patients, between May, 2008, and December, 2010, at Luang Namtha provincial hospital in northwest Laos (n=1390), and between September, 2008, and December, 2010, at Salavan provincial hospital in southern Laos (n=548). Eligible participants were aged 5–49 years with fever (≥38°C) lasting 8 days or less and were eligible for malaria testing by national guidelines. Findings: With conservative definitions of cause, we assigned 799 (41%) patients a diagnosis. With exclusion of influenza, the top five diagnoses when only one aetiological agent per patient was identified were dengue (156 [8%] of 1927 patients), scrub typhus (122 [7%] of 1871), Japanese encephalitis virus (112 [6%] of 1924), leptospirosis (109 [6%] of 1934), and bacteraemia (43 [2%] of 1938). 115 (32%) of 358 patients at Luang Namtha hospital tested influenza PCR-positive between June and December, 2010, of which influenza B was the most frequently detected strain (n=121 [87%]). Disease frequency differed significantly between the two sites: Japanese encephalitis virus infection (p=0·04), typhoid (p=0·006), and leptospirosis (p=0·001) were more common at Luang Namtha, whereas dengue and malaria were more common at Salavan (all p<0·0001). With use of evidence from southeast Asia when possible, we estimated that azithromycin, doxycycline, ceftriaxone, and ofloxacin would have had significant efficacy for 258 (13%), 240 (12%), 154 (8%), and 41 (2%) of patients, respectively. Interpretation: Our findings suggest that a wide range of treatable or preventable pathogens are implicated in non-malarial febrile illness in Laos. Empirical treatment with doxycycline for patients with undifferentiated fever and negative rapid diagnostic tests for malaria and dengue could be an appropriate strategy for rural health workers in Laos. Funding: Wellcome Trust, WHO–Western Pacific Region, Foundation for Innovative New Diagnostics, US Centers for Disease Control and Prevention