South American haemorrhagic fevers

Initial prevention strategies include:

• Reduction in rodent populations

  • An increase in urban cases of Bolivian haemorrhagic fever occurred in the early 1960s prior to which the disease had been predominantly found in rural areas. This was due to a significant increase in the rodent population in several small towns, which is thought to have occurred as a result of a marked reduction in the feline population due to toxicity from high exposure to the insecticide DDT (dichlorodiphenyltrichloroethane). This outbreak was controlled when the rodent reservoir was identified, and rodenticides and systematic trapping of rodents occurred alongside importation of a feline population[2]Patterson M, Grant A, Paessler S. Epidemiology and pathogenesis of Bolivian hemorrhagic fever. Curr Opin Virol. 2014;5:82-90. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4028408 http://www.ncbi.nlm.nih.gov/pubmed/24636947?tool=bestpractice.com

• Early identification and appropriate isolation of cases to reduce the risk of transmission to community contacts and healthcare workers, including:

  • Community education and awareness of the condition, including practicing good hygiene measures (e.g., hand washing, appropriate disposal of waste products)

  • Education of healthcare workers in rural health centres in endemic areas

  • Provision of personal protective equipment (PPE) for healthcare workers in rural areas and referral centres, with appropriate education in donning and doffing, sharp safety, handling of patient specimens, and safe disposal of waste. The World Health Organization (WHO), US Centers for Disease Control and Prevention (CDC), NHS England, and UK Health Security Agency (UKHSA) have published guidance on the use of PPE in a clinical context. The WHO guidance is directed at low- or middle-income nations, whereas the CDC and UKHSA guidance is for high-income nations:[26]World Health Organization. Guidance: steps to remove personal protective equipment. 2014 [internet publication]. http://www.who.int/csr/disease/ebola/remove_ppequipment.pdf?ua=1 ​​[27]Centers for Disease Control and Prevention. Guidance on personal protective equipment (PPE) to be used by healthcare workers during management of patients with confirmed Ebola or persons under investigation (PUIs) for Ebola who are clinically unstable or have bleeding, vomiting, or diarrhea in US hospitals, including procedures for donning and doffing PPE. August 2018 [internet publication]. https://www.cdc.gov/vhf/ebola/healthcare-us/ppe/guidance.html ​​​

    • WHO: how to put on and how to remove personal protective equipment (PPE) Opens in new window

    • CDC: guidance on personal protective equipment (PPE) for evaluating patients suspected to have selected viral hemorrhagic fevers who are clinically stable and do not have bleeding, vomiting, or diarrhea Opens in new window

    • NHS England: addendum on high consequence infectious disease (HCID) personal protective equipment (PPE) Opens in new window

    • UK Health Security Agency: high consequence infectious diseases (HCID) Opens in new window​​​

  • Appropriate facilities to transport and isolate patients and/or diagnostic samples

  • Appropriate laboratory facilities with biosafety levels (BSL) 3 or 4

  • Facilities for molecular diagnostics or suitably equipped laboratories to allow sample inactivation before processing at BSL-2 to undertake diagnostics and protect laboratory staff. Note that deliberate propagation or virus isolation requires a BSL-4 capability. All SAHF viruses are classed as BSL-4 pathogens.

Vaccines:

• A vaccine is available in Argentina for Argentine haemorrhagic fever. Developed in the 1980s, and known as Candid#1, it has significantly reduced the incidence of Argentine haemorrhagic fever in endemic areas where a large proportion of the at-risk population have been immunised.[2]Patterson M, Grant A, Paessler S. Epidemiology and pathogenesis of Bolivian hemorrhagic fever. Curr Opin Virol. 2014;5:82-90. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4028408 http://www.ncbi.nlm.nih.gov/pubmed/24636947?tool=bestpractice.com [5]Enria DA, Briggiler AM, Feuillade MR. An overview of the epidemiological, ecological and preventive hallmarks of Argentine haemorrhagic fever (Junin virus). Bulletin Institut Pasteur. 1998;96:103-114.[28]Olschläger S, Flatz L. Vaccination strategies against highly pathogenic arenaviruses: the next steps toward clinical trials. PLoS Pathog. 2013;9:e1003212. http://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1003212 http://www.ncbi.nlm.nih.gov/pubmed/23592977?tool=bestpractice.com [29]Kerber R, Reindl S, Romanowski V, et al. Research efforts to control highly pathogenic arenaviruses: a summary of the progress and gaps. J Clin Virol. 2015;64:120-127. http://www.ncbi.nlm.nih.gov/pubmed/25549822?tool=bestpractice.com

• There appears to be some cross coverage of Candid#1 for Bolivian haemorrhagic fever, which has been demonstrated in studies involving non-human primates.[2]Patterson M, Grant A, Paessler S. Epidemiology and pathogenesis of Bolivian hemorrhagic fever. Curr Opin Virol. 2014;5:82-90. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4028408 http://www.ncbi.nlm.nih.gov/pubmed/24636947?tool=bestpractice.com [29]Kerber R, Reindl S, Romanowski V, et al. Research efforts to control highly pathogenic arenaviruses: a summary of the progress and gaps. J Clin Virol. 2015;64:120-127. http://www.ncbi.nlm.nih.gov/pubmed/25549822?tool=bestpractice.com Studies of Candid#1 for Bolivian haemorrhagic fever in humans have not been carried out.

• No other vaccine candidates are available for the other SAHFs.

All SAHFs are notifiable diseases to the relevant public health authority.

Although community person-to-person transmission is rare for the SAHFs, contact tracing and monitoring of contacts for symptoms during the incubation period (i.e., approximately 3-16 days) is essential to reduce any onward community transmission and ensure rapid isolation and treatment if symptoms appear.

There is no known prophylaxis that can be administered to contacts. The antiviral drug ribavirin could be a potential therapy for prophylaxis as it has been used as prophylaxis in Lassa fever; however, there are no substantial clinical data for its efficacy in Lassa fever and no data for SAHF viruses.[55]Hadi CM, Goba A, Khan SH, et al. Ribavirin for Lassa fever postexposure prophylaxis. Emerg Infect Dis. 2010;16:2009-2011. http://wwwnc.cdc.gov/eid/article/16/12/10-0994_article http://www.ncbi.nlm.nih.gov/pubmed/21122249?tool=bestpractice.com Although the Argentine haemorrhagic fever vaccine, Candid#1, has not been studied in contacts, and community transmission of this disease from person to person is rare, it may be warranted in high-risk contacts of Argentine haemorrhagic fever who have not previously been vaccinated. Studies in non-human primates indicate that the Candid#1 vaccine may also provide protection in Bolivian haemorrhagic fever.[2]Patterson M, Grant A, Paessler S. Epidemiology and pathogenesis of Bolivian hemorrhagic fever. Curr Opin Virol. 2014;5:82-90. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4028408 http://www.ncbi.nlm.nih.gov/pubmed/24636947?tool=bestpractice.com [29]Kerber R, Reindl S, Romanowski V, et al. Research efforts to control highly pathogenic arenaviruses: a summary of the progress and gaps. J Clin Virol. 2015;64:120-127. http://www.ncbi.nlm.nih.gov/pubmed/25549822?tool=bestpractice.com As risk of nosocomial and person-to-person transmission appears to be higher for this disease compared with the other SAHFs, immunisation of Bolivian haemorrhagic fever contacts with Candid#1 may be considered in the future if safety and immunogenicity are demonstrated in humans.[2]Patterson M, Grant A, Paessler S. Epidemiology and pathogenesis of Bolivian hemorrhagic fever. Curr Opin Virol. 2014;5:82-90. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4028408 http://www.ncbi.nlm.nih.gov/pubmed/24636947?tool=bestpractice.com ​ However, the vaccine is only currently available in Argentina.​