Concurrent infections of dengue viruses serotype 2 and 3 in patient with severe dengue from Jakarta, Indonesia

Objective: To describe the clinical manifestation of patient with severe dengue, to identify the serotypes and genotypes of dengue viruses(DENV) which concurrently infecting the patient, and to explore the possible relationship of severe dengue with the concurrent infection of DENV. Methods: Dengue diagnosis was performed using NS1 antigen detection and Ig G/Ig M ELISA. Standard clinical and laboratory examinations were performed to obtain the clinical and hematological data. DENV concurrent infections were detected and confirmed using RT-PCR and DENV Envelope gene sequencing. Phylogenetic analyses were performed to determine the genotypes of the viruses. Results: The patient was classified as having severe dengue characterized by severe plasma leakage, hemorrhage, and organ damage involving lung, liver, and kidney. Concurrent infection of DENV serotype 2 and 3 was observed. The infecting DENV-2 virus was grouped into Cosmopolitan genotype while DENV-3 virus was classified into Genotype Ⅰ. Both viruses were closely related to isolates that were endemic in Jakarta. Viremia measurement was conducted and revealed a significantly higher virus titer of DENV-3 compared to DENV-2. Conclusions: The occurrence of multi-serotype DENV infections was presented in a patient with severe clinical manifestation in Indonesia. The hyperendemicity of dengue in Indonesia may contribute to the DENV concurrent infections cases and may underlie the severity of the disease.

Clinical features of severe malaria:Protective effect of mixed plasmodial malaria

Objective: To investigate clinically severe malaria patients with Plasmodium falciparum(P. falciparum), Plasmodium vivax(P. vivax) and mixed species infections.Methods: This study was conducted at Dr. Saiful Anwar General Hospital, Malang,Indonesia, from December 2011 to May 2013. Twenty nine patients(mean age of 41 years, 22% female), who suffered from severe malaria according to World Health Organization criteria(major and minor) and other criteria based on previous studies, were selected by consecutive sampling. Blood samples were obtained at admission from peripheral blood for microscopic diagnostic, nested PCR and laboratory examination of blood chemistry. Laboratory results were compared between the groups and correlated to each other.Results: From 29 samples, eight(28%) were diagnosed as P. falciparum mono-infection,12(41%) as P. vivax mono-infection and nine(31%) as mixed infections, confirmed by PCR. Cerebral malaria occurred in P. falciparum or mixed species infection only. Parasitaemia was highest in P. falciparum mono-infection. Mean haemoglobin was significantly lower in P. falciparum than P. vivax infection(P = 0.01). Mean thrombocyte count(77 138/m L) was low in all groups. Mean urea, creatinine, total and direct bilirubin were significantly higher in P. falciparum mono-infection compared to other groups, whereas aspartate aminotransferase and alanine aminotransferase showed no significant differences. Parasitaemia was positively correlated with an increase in urea, creatinine, bilirubin and leucocytosis in all species.Conclusions: Both Plasmodium species can solely or in combination cause severe malaria. Mixed infection was generally more benign than P. falciparum mono-infection and seemed to have some protective effects.

Study on DNA Immunization by Recombinants Encoding Japanese Encephalitis Virus prME and E Proteins

To study the expression characteristic of Japanese encephalitis virus (JEV) prME and E proteins and the efficacy of DNA immunization by different recombinant plasmids containing JEV prME (2001 bp) and E (1500 bp) genes, two recombinants (pJME and pJE) containing JEV prME and E genes fused with FLAG were constructed and then transfected into HepG2 and COS-1 cells by liposome fusion. The expression feature of FLAG-prME (about 72 kDa) and FLAG-E (about 54 kDa) proteins in transfected cells were analyzed by Western blot and two antibody systems (anti-FLAG and anti-E). BALB/c mice were immunized with 100 μg of two kinds of recombinants by intramuscular injection, and JEV JaGAr-01 strains (10 5 PFU/100 μl)were given to BALB/c mice by intraperioneal injection 3 wk after twice DNA immunization by a lethal virus challenge. BALB/c mice were observed for 21 days after challenge. 80% plaque reduction neutralization test was performed to titrate neutralization antibody before and after viral challenge. It was found that the expression of proteins associated with pJME and pJE was determined in transfected cells with anti-FLAG and a new protein of 11 kDa was detected in HepG2 and COS-1 cells transfected with pJME. Only E (53 kDa) protein was identified as transfected with pJME using anti-E. Higher level of neutralization antibodies and the efficacy of protective immunity were induced with pJME immunization, and were similar to those induced by inactivated Japanese encephalitis vaccine, but were better than those induced with pJE. It concludes that the expression level from prM to E proteins of JEV is different in vitro, and the in vitro expression efficiency of pJME was better than that of pJE. FLAG-prME protein expressed by pJME could be cleaved by peptidase from host. The efficacy of DNA immunization is correlated to the expression characterization of related proteins expressed in vitro.