BackgroundInfectious diseases of the central nervous system (CNS) remain common and life-threatening, especially in developing countries. Knowledge of the aetiological agents responsible for these infections is essential to guide empiric therapy and develop a rational public health policy. To date most data has come from patients admitted to tertiary referral hospitals in Asia and there is limited aetiological data at the provincial hospital level where most patients are seen.MethodsWe conducted a prospective Provincial Hospital-based descriptive surveillance study in adults and children at thirteen hospitals in central and southern Viet Nam between August 2007– April 2010. The pathogens of CNS infection were confirmed in CSF and blood samples by using classical microbiology, molecular diagnostics and serology.ResultsWe recruited 1241 patients with clinically suspected infection of the CNS. An aetiological agent was identified in 640/1241 (52%) of the patients. The most common pathogens were Streptococcus suis serotype 2 in patients older than 14 years of age (147/617, 24%) and Japanese encephalitis virus in patients less than 14 years old (142/624, 23%). Mycobacterium tuberculosis was confirmed in 34/617 (6%) adult patients and 11/624 (2%) paediatric patients. The acute case fatality rate (CFR) during hospital admission was 73/617 (12%) in adults and to 42/624 (7%) in children.ConclusionsZoonotic bacterial and viral pathogens are the most common causes of CNS infection in adults and children in Viet Nam.

Increasing drug resistance in Plasmodium falciparum to artemisinins and their ACT partner drugs jeopardises effective antimalarial treatment. Resistance is worst in the Greater Mekong Subregion. Monitoring genetic markers of resistance can help to guide antimalarial therapy. Markers of resistance to artemisinins ( PfKelch mutations), mefloquine (amplification of P. falciparum multidrug resistance-1, PfMDR1, ), and piperaquine ( PfPlasmepsin2/3 amplification and specific P. falciparum chloroquine resistance transporter, PfCRT, mutations) were assessed in 6,722 P. falciparum samples from Vietnam, Lao PDR, Cambodia, Thailand, Myanmar between 2007 and 2019. Against a high background prevalence of PfKelch mutations, PfMDR1 and PfPlasmepsin2/3 amplification closely followed regional drug pressures over time. PfPlasmepsin2/3 amplification preceded piperaquine-resistance associated PfCRT mutations in Cambodia, and reached a peak prevalence of 23/28 (82%) in 2015. This declined to 57/156 (38%) after changing first-line treatment away from dihydroartemisinin-piperaquine to artesunate-mefloquine (ASMQ) between 2014 and 2017. PfMDR1 amplification increased from 0/293 (0%) between 2012 and 2017 to 12/156 (8%) in 2019. Amplification of PfMDR1 and PfPlasmepsin2/3 in the same parasites was extremely rare (4/6,722; 0.06%) and dispersed over time. Mechanisms conferring mefloquine and piperaquine resistance may be counterbalancing. This supports the development of ASMQ plus piperaquine as a triple artemisinin combination therapy.

IntroductionAnti-NMDA receptor encephalitis is increasingly recognised as an important differential diagnosis in patients with encephalitis of unknown aetiology. We report the first case series of patients diagnosed in Vietnam.MethodsSamples of CSF from patients with presumed encephalitis but negative microbiological investigations, who exhibited dyskinesia, autonomic instability or psychosis were tested for antibodies against the NR1 subunit of the glutamate (type-NMDA) receptor using an indirect immunofluorescence assay.ResultsOf 99 patients admitted with all-cause encephalitis over an 18 month period, 9.1% (n = 9 patients, 5 female, median age 28 years) had confirmed NMDAR encephalitis. All patients were admitted from one mental health hospital, and the incidence may therefore be an underestimate. Common features included reduction in speech (n = 9), catatonia (n = 9), convulsions (n = 7), dyskinesia (n = 9), rigidity (n = 9) and autonomic dysfunction (n = 7). Aside from a modest lymphocytic pleocytosis, routine CSF analysis was usually normal. No female patient had ovarian teratoma detected by abdominal ultrasound. Most patients were treated with high dose corticosteroids, and one patient received intravenous immunoglobulin. The median duration of hospitalization was 75 days and no patient died during admission.ConclusionsAnti-NMDA receptor encephalitis is an important differential diagnosis to consider for patients presenting with acute onset psychiatric symptoms, who develop ensuing seizures, movement or autonomic disorder in Vietnam. A stronger evidence base for management and access to second line immunotherapy agents may help to reduce morbidity from this disease.

BackgroundAnthelmintics are one of the more commonly available classes of drugs to treat infections by parasitic helminths (especially nematodes) in the human intestinal tract. As a result of their cost-effectiveness, mass school-based deworming programs are becoming routine practice in developing countries. However, experimental and clinical evidence suggests that anthelmintic treatments may increase susceptibility to other gastrointestinal infections caused by bacteria, viruses, or protozoa. Hypothesizing that anthelmintics may increase diarrheal infections in treated children, we aim to evaluate the impact of anthelmintics on the incidence of diarrheal disease caused by viral and bacterial pathogens in school children in southern Vietnam.Methods/designThis is a randomized, double-blinded, placebo-controlled trial to investigate the effects of albendazole treatment versus placebo on the incidence of viral- and bacterial-induced diarrhea in 350 helminth-infected and 350 helminth-uninfected Vietnamese school children aged 6–15 years. Four hundred milligrams of albendazole, or placebo treatment will be administered once every 3 months for 12 months. At the end of 12 months, all participants will receive albendazole treatment. The primary endpoint of this study is the incidence of diarrheal disease assessed by 12 months of weekly active and passive case surveillance. Secondary endpoints include the prevalence and intensities of helminth, viral, and bacterial infections, alterations in host immunity and the gut microbiota with helminth and pathogen clearance, changes in mean z scores of body weight indices over time, and the number and severity of adverse events.DiscussionIn order to reduce helminth burdens, anthelmintics are being routinely administered to children in developing countries. However, the effects of anthelmintic treatment on susceptibility to other diseases, including diarrheal pathogens, remain unknown. It is important to monitor for unintended consequences of drug treatments in co-infected populations. In this trial, we will examine how anthelmintic treatment impacts host susceptibility to diarrheal infections, with the aim of informing deworming programs of any indirect effects of mass anthelmintic administrations on co-infecting enteric pathogens.Trial registrationClinicalTrials.gov: NCT02597556. Registered on 3 November 2015.Electronic supplementary materialThe online version of this article (doi:10.1186/s13063-016-1406-1) contains supplementary material, which is available to authorized users.