Chickenpox outbreak in a tribal and industrial zone from the Union Territory of Dadra and Nagar Haveli, India.

During 9th December 2016 and 12th February 2017, 149-chickenpox cases were reported in a tribal and industrial zone of Rakholi (n = 80) and Surangi (n = 69) villages from Union Territory of India. An epidemiological investigation was performed to assess the characteristics and determinants of the chickenpox outbreak. Overall, the attack rate per 100 population in Rakholi village (n = 1757) was 4.5% and 19.1% in Surangi village (n = 360). Ages of the cases were ranged from 6 months to 55 years and there were 53 females and 96 males. For the laboratory investigations, 25 serum samples, three urine specimens, three throat swabs and six blister/skin swabs were collected from 37-suspected chickenpox cases. Altogether, 30-suspected cases were laboratory confirmed by either IgM EIA or varicella zoster virus (VZV) DNA PCR. Both VZV-specific IgM and IgG antibodies were detected in 19-suspected cases. Two suspected cases showed the presence of VZV-specific IgG antibodies but not IgM antibodies. On the contrary, three suspected cases showed VZV-specific IgM but not IgG antibodies. Overall, 31 of 37-suspected cases (including one equivocal case) were laboratory confirmed. The partial sequencing of ORF-28 gene of VZV revealed circulation of clade-1 viruses. In conclusion, this investigation provides detail information about the chickenpox outbreak in the tribal and industrial setting from India. Furthermore, the study emphasises the need to investigate more chickenpox outbreaks in different parts of India.

Detection of Mycoplasma species in cell culture by PCR and RFLP based method: effect of BM-cyclin to cure infections.

PURPOSE: A two-stage nested polymerase chain reaction (PCR) assay system was described that amplifies the 16S-23S rRNA spacer region sequences of Mycoplasma and Acholeplasma infections in cell cultures and virus stocks. METHODS: Established cell lines and virus stocks were screened for the presence of Mycoplasma by using nested PCR using two sets of outer and inner primers, amplifies 16S-23S rRNA. PCR and restriction fragment length polymorphism (RFLP) assay was used to detect and identify most of the species-specific Mycoplasmas involved in cell cultures and virus stock contaminants. Infected cultures detected by PCR-RFLP were further treated with BM-cyclin (5 microg/mL) and passaged for three times and tested for Mycoplasma infections by PCR-RFLP. RESULTS: Mycoplasma pirum and Mycoplasma orale infections were detected by nested PCR. Species specificity was identified by using RFLP of Vsp I, Cla I and Hin dIII restriction enzymes. Mycoplasma infections were cured by treatment with BM-cyclin. This was further confirmed by non-amplification of PCR amplimers in BM-cyclin treated vs. non-treated cultures. CONCLUSIONS: Regular monitoring of cell cultures for Mycoplasma infections and identification of species-specific Mollicutes will identify the source of contaminations. This approach can be used for quality control of the biological reagents used in cell culture and virology laboratories.