Ross River virus infection surveillance in the Greater Perth Metropolitan area – has there been an increase in cases in the winter months?
DOI:
https://doi.org/10.33321/cdi.2014.38.20Keywords:
Ross River virus, surveillance, notifications, serologyAbstract
An increase in off-season (June to September) Ross River virus (RRV) notifications from the greater Perth metropolitan area was observed from 2006 to 2009. We investigated the increase to determine whether it is likely to have reflected a true increase in off-season cases. A single positive RRV IgM test result is sufficient for RRV notification but where follow-up testing was performed, the positive predictive value of an IgM test where IgG was negative was very low in the off-season and also in the season when using the only commercially available test kit. The increase in off-season notifications was not associated with an increase in off-season testing. Some Perth laboratories use more stringent notification criteria than the nationally agreed RRV case definition, and the geographical distribution of samples tested varies between laboratories. Our findings make a strong case to change the nationally agreed case definition for RRV to not accept a single IgM positive test result as laboratory definitive evidence where the IgG is negative. Our study also identified a range of challenges in interpreting changes in seasonal patterns and geographical distribution of RRV. Any such observed changes should be investigated through further data analysis and/or mosquito trapping and testing in order to assess validity. Commun Dis Intell 2014;38(2):E115–E122.
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Mackenzie JS, Lindsay MD, Coelen RJ, Broom AK, Hall RA, Smith DW. Arboviruses causing human disease in the Australasian zoogeographic region. Arch Virol 1994;136(3–4): 447–467.
Flexman JP, Smith DW, Mackenzie JS, Fraser JR, Bass SP, Hueston L, et al. A comparison of the diseases caused by Ross River virus and Barmah Forest virus. Med J Aust 1998;169(3):159–163.
Harley D, Sleigh A, Ritchie S. Ross River virus transmission, infection, and disease: A cross-disciplinary review. Clin Microbiol Rev 2001;14(4): 909–932.
Department of Health. Australian national notifiable diseases case definitions. Ross River virus infection case definition. [online] Accessed January 2014. Available from: http://www1.health.gov.au/internet/main/publishing.nsf/Content/cda-surveil-nndss-casedefs-cd_rrv.htm
Aaskov JG, Davies CE. An immunofluorescence assay for human antibodies to Ross River virus. J Immunol Methods 1979; 25(1):37–41.
Smith DW, Speers DJ, Mackenzie JS. The viruses of Australia and the risk to tourists. Travel Med Infect Dis 2011; 9(3):113–125.
Harley D, Sleigh A, Ritchie S. Ross River virus transmission, infection, and disease: a cross-disciplinary review. Clin Microbiol Rev 2001;14(4): 909–932, table of contents.
Rich G, McKechnie J, McPhan I, Richards B. Laboratory diagnosis of Ross River virus infection. Commun Dis Intell 1993;17:208–209.
Cashman P, Hueston L, Durrheim D, Massey P, Doggett S, Russell RC. Barmah Forest virus serology; implications for diagnosis and public health action. Commun Dis Intell 2008;32(2):263–266.
Carter IWJ, Smythe LD, Fraser JRE, Stallman ND, Cloonan MJ. Detection of Ross River virus immunoglobulin-M antibodies by enzyme-linked immunosorbent-assay using antibody class capture and comparison with other methods. Pathology 1985;17(3): 503–508.
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