This is found in wild rats around the world so DO NOT bring in wild rats, and keep wild rodents away from your animals as well
as their food and bedding. Rats do not display symptoms or get sick with this virus. Quarantining new animals won’t
determine if they carry this, only laboratory testing
Charles River; antibody
test). There have been very few reports of human infections and majority of the people that get this do not show symptoms.
U.K. Seoul Virus
CDC/State Health Articles
Diagnostic Testing Info.
- Hantavirus Found In Pet Rats In The U.K. (2013)
- Pet rats as a source of hantavirus in England and Wales,
2013 - 1. Jameson L, Taori S, Atkinson B, Levick P, Featherstone C, van der Burgt G, et al. Eurosurveillance, Volume 18, Issue 9,
28 February 2013. An owner and his two pet rats in Wales tested positive for a strain of SEOV (named Cherwell); 7 of 21 of the breeder’s
rats (supplied the 2 pet rats) were positive for same strain and her husband tested positive for past infection (late 2011); of 4 people tested,
2 hospitalized, 1 positive with no symptoms, 1 negative; all rats euthanized on order to further scientific understanding of hantavirus infection
in pet rats; U.K. has two strains – Humbar (Jan. 2013) and Cherwell (Feb. 2013). (PDF)
- High prevalence of Seoul hantavirus in a breeding colony of pet rats - L. M. McElhinney, et al.
Epidemiol Infect. 2017 Nov;145(15):3115–3124. Further investigation of case of SEOV positive rats in Wales and England
(Cherwell and Cheltenham); some of the rats had very high antibody titres of 10240; each hantavirus restricted to single host species.
infection in people: sero-surveillance study in England - from Public Health England (Sept. 2014). Of the rat fancy rat breeders tested,
32.9% were positive; urine samples were collected from rats but results not given. PDF
- HAIRS risk assessment: hantavirus - from
Public Health England (Feb. 2016). Is endemic in the U.K.; people with pet rats most as risk; at least 100,000 pet rats in country
(2014 survey) but number of diagnosed infections remains small; not highly infectious in humans; humans and other species of animals
dead-end hosts; persistently infected rodents do not excrete large amounts of virus; vaccine used in China and Korea but no licensed
vaccines available in other regions, one DNA-based vaccine for the PUUV and HTNV viruses has reached phase 1 clinical trial
- Pets, Purity and Pollution: Why Conventional Models of Disease Transmission
Do Not Work for Pet Rat Owners - Charlotte Robin, Elizabeth Perkins, Francine Watkins, and Robert Christley. Int. J. Environ.
Res. Public Health 2017, 14(12), 1526. In-depth, semi-structured interviews of 7 pet rat owners on how they view their pets rats
in light of the Seoul Hantavirus 2012 outbreak in the U.K.
- Reducing the risk of human infection from pet rodents (PDF) - from the U.K. Health Protection Agency (now known as Public Health England) (Feb. 2013)
Reducing the risk of human infection from pet rodents (PDF) - brochure from the U.K. Health Protection Agency (now known as Public Health England) (2013)
- CDC/State Health Articles
- CDC Press Release: CDC Assisting Illinois and Wisconsin Investigation of
Seoul Virus Outbreak Associated with Home-based Rat-Breeding Facilities - Hantavirus found in pet rats in WI and IL (Jan. 20, 2017)
- CDC Press Release: Investigation of Seoul Virus Outbreak Associated with
Home-based, Rat-breeding Facilities in Wisconsin and Illinois - Hantavirus found in pet rats in WI and IL (Jan. 24, 2017). IgM
detectable within a few days after symptom onset and detectable for approximately 2 to 3 months; IgG detected within a week after
symptom onset and can remain detectable for years.
- CDC Press Release: Multi-state Outbreak of Seoul Virus -
highlight updates going back to Jan. 18, 2017
- IL: Illinois
Department of Public Health Reports Six Cases Of Viral Illness Linked To Ratteries - Jan. 23, 2017. Six people in Illinois tested
positive from exposure to 2 IL ratteries.
- CDC conference call notes - CDC
conference call hosted by PIJAC Jan. 31, 2017, with pet owners, feeder breeders, and commercial
breeders regarding the Seoul Hantavirus outbreak in the Midwest; IDEXX test results similar to CDC; Seoul virus has a short environmental
lifespan outside host—virus deactivated by UV light, sunlight, commercial disinfectants, soaps, detergent, bleach; newborn rats get
temporary immunity via maternal antibodies (PDF)
call summary: Seoul virus and pet rats - Summary of Feb. 3, 2017, call between CDPHE and Colorado rattery owners. Negative rats
don’t have to be culled—isolate after first test, then retest in 4 weeks, then again 4 weeks later; CDC has no plans
to validate Charles River test, only IDEXX. (archived page) UPDATE:
Charles River Laboratories serologic test (EZ-Spot®)
is presently being validated by CDC.
- Notes from the Conference Call with CDC,
February 1, 2017 - and the Rat Fancy Think Tank Work Group; virus doesn’t last long in environment—killed by sunlight,
soap, detergents, disinfectants, bleach. (PDF)
- FAQs: Seoul virus - CDC questions and
answers; IDEXX serologic (antibody) test (Opti-Spot™) and molecular (PCR) test for Seoul virus in rats yield results closely similar
to those for CDC; serologic testing is the most accurate
- Cleaning Up After Pet Rodents to
Reduce the Risk of Seoul Virus Infection - CDC article
- Outbreak of Seoul Virus Among Rats and Rat Owners — United States
and Canada, 2017 - February 2, 2018, outbreak report
- Hantavirus - The Center for Food Security & Public Health,
Iowa State University (2009). Has disinfection information–susceptible to disinfectants, detergents, heating, drying; recently
infected animals tend to shed larger amounts of virus, virus shedding decreases by 8 weeks after infection. (PDF)
- Wounding: The Primary Mode Of Seoul Virus Transmission Among Male Norway Rats -
Ella R. Hinson, Scott M. Shone, M. Christine Zink, Gregory E. Glass, and Sabra L. Klein. Am J Trop Med Hyg March 2004 vol. 70
no. 3 310–317. Study done with wild rats in Maryland; only during limited time are animals shedding virus and capable of
infecting uninfected individuals; virus shedding typically occurs immediately after infection followed by a chronic period of
infection characterized by active immune responses in the absence of virus shedding; during this time of chronic infection animals
often fail to transmit virus to uninfected cage mates; adult males/aggressive males more likely to have virus due to wounding and
to shed virus than young rats.
- Association of intraspecific wounding
with hantaviral infection in wild rats (Rattus norvegicus) - G. E. Glass, J. E. Childs, G. W. Korch, and J. W. LeDuc.
Epidemiol Infect. 1988 Oct; 101(2): 459–472. 1988 article on 6-year study done with wild rats in Baltimore, MD; infection
associated with wounding, severe body wounds had high titres (high ≥128; ≥32 considered positive, 32 to <128 considered low
seropositive), wounding is the primary route of transmission, sexually mature males most affected, rats sexually mature after
200 g (seroconversion median age was 6 months), most seroconversions occurred during spring and autumn when wounding peaked
with reproductive activity, young rarely wounded/seropositive. (PDF)
- Seoul virus infection increases aggressive behaviour
in male Norway rats - Sabra L.Klein, M.Christine Zink, Gregory E. Glass. Animal Behaviour. Volume 67, Issue 3, March 2004,
Pages 421–429. Male lab rats tested 30 days after inoculation (i.e. during the persistent phase of infection) spent more time
engaged in aggression than either uninfected males or males tested during the acute phase of infection (i.e. 15 days after infection);
virus shedding, however, was not correlated with aggression.
- Epizootiology of Hantavirus infections in Baltimore: isolation
of a virus from Norway rats, and characteristics of infected rat populations - James E. Childs, George W. Korch, Gregory E.
Glass, James W. LeDuc, and Keerti V. Shah. Am J Epidemiol. 1987 Jul;126(1):55–68. A 6-year-study of wild Norway rats in
Baltimore, MD found Hantaan-related virus enzootic in the city; older rats more likely to be seropositive and have higher titers
than younger rats (a titer of 1:32 considered positive; 48.2% were positive); varied by season with spring (March to May) being low
and increased linearly through winter (Dec. to Jan.); Wistar rats inoculated with the virus showed
seroconversion at day 26–30 with majority by day 40–44. (PDF)
- Sex Differences in Seoul Virus Infection Are Not Related to
Adult Sex Steroid Concentrations in Norway Rats - Sabra L. Klein, Brian H. Bird, and Gregory E. Glass. J Virol.
2000 Sep; 74(17): 8213–8217. Male Long Evans rats inoculated with Seoul virus had higher IgG on days 20, 30, and 40
postinoculation than females; males shed virus in saliva and feces longer; more males shed virus in saliva on day 10 and 30
and in feces on day 30 than females; antibody detectable 15 to 30 days postinoculation with no difference between males and
females; testing done on intact and gonadectomized males and females; male rats higher IgG2a than females on days 30 and 40
postinoculation despite hormone manipulation; positive was optical density ≥0.100
- Sex Differences In Immune Responses And Viral Shedding
Following Seoul Virus Infection In Norway Rats - S L Klein, B H Bird, G E Glass. Am J Trop Med Hyg. 2001 Jul;65(1):57–63.
Long Evans lab rats tested; antibodies develop typically by day 30 after inoculation; males higher levels than females of IgG titers
for Seoul virus 40 days post-inoculation; not all shed virus; more males shed virus in saliva, or multiple routes than females;
high levels of testosterone increase fighting; castrated vs. intact males similar anti-Seoul virus IgG21 responses; sexes are
equally susceptible to infection but have different immune responses so males more likely to shed virus
- Environmental and Physiological Factors Associated
with Seoul Virus Infection Among Urban Populations of Norway Rats - Sabra L. Klein, Brian H. Bird, Randy J. Nelson, Gregory
E. Glass. Journal of Mammalogy, Volume 83, Issue 2, 1 May 2002, pages 478–488. Study of wild-caught rats in Baltimore,
MD from 1996–2000; approximately 50% infected with Seoul virus; adults and older rats more likely to be infected and have
higher antibody responses than younger adults; this study found females higher IgG than males [compared to other studies where
males had more]; seasonal changes not observed [one study found changes with more in spring and autumn, another study was less
in spring to more in winter]; antibody changes also not observed in changes in photoperiod but higher IgG responses found during
low temps.; antibody positive if optical density was ≥0.100; physiological and behavioral changes with sexual maturity (body
mass not age) best predictors of Seoul virus
- A survey of zoonotic pathogens carried by Norway rats in Baltimore,
Maryland, USA - Epidemiol Infect. 2007 Oct; 135(7): 1192–1199. 201 wild rats were tested during 2005–2006 for
panel of viruses, bacteria, and parasites; found 57.7% had SEOV, 87.9% had roundworms, and more than a third had tapeworms,
among other things; LCMV was not found (natural LCMV infection not reported in Norway rats and does
not appear to be transmitted from rats to humans); the presence of antibodies against Seoul virus was not correlated with the
likelihood of being infected with any of the other pathogens tested; the presence of antibody does not necessarily indicate an
- Aerosol Transmission of Hantaan and Related Viruses
to Laboratory Rats - Edwin O. Nuzum, Cynthia A. Rossi, Edward H. Stephenson, James W. LeDuc. The American Journal of
Tropical Medicine and Hygiene, Volume 38, Issue 3, May 1988, p. 636–640. Study done on 12–16-week-old female Wistar
Norway rats using intramuscular and aerosol routes of infection; positive titers were ≥32; intracage transmission did not occur;
wounding from infectious saliva a factor in transmission; intramuscular exposure had higher antibody titers and seroconversion rates.
- Experimental Transmission Of
Hantavirus Infection In Laboratory Rats - Kayoko Dohmae, Masaru Okabe, Yoshitake Nishimune. The Journal of Infectious Diseases,
Volume 170, Issue 6, 1 December 1994, pages 1589–1592. Normal rats did not transmit Hantavirus to normal cagemates but did to Rowett
nude rats (T-cell deficient); nude rats highly susceptible to the Hantavirus infection and gave it to normal cagemates.
- Old World Hantaviruses in Rodents in New Orleans, Louisiana -
Cross RW, Waffa B, Freeman A, et al. Am J Trop Med Hyg. 2014 May 7; 90(5): 897–901. 3.4% of wild brown [Norway] rats tested
positive compared to 1980s when over 30% trapped in New Orleans tested positive; over 25 years since first discovery suggests stable
endemicity; found in almost all cities in the world; each virus specific to host species.
- Immunological Mechanisms Mediating Hantavirus Persistence in
Rodent Reservoirs - Judith D. Easterbrook and Sabra L. Klein, PLoS Pathog. 2008 Nov; 4(11): e1000172. Rats are not
immunosuppressed with SEOV; antibodies detectable after the first 2 weeks of infection, increases for next 4–6 weeks,
then declines; acute phase first 2–3 weeks of infection; maternal antibodies protect young first 2 months of life; T-cells
contribute to control of virus replication.
- Old-World Hantaviruses: Global Status: 2017 edition - Dr. Stephen Berger, GIDEON Informatics, Inc.,
Hantavirus Hantavirus infections, diagnosis and treatment from Reagena (archived page)
- Maternal Transfer of Hantavirus
Antibodies in Rats - Kayoko Dohmae and Yoshitake Nishimune. Laboratory Animal Science, Vol 48, No 4, August 1998. Japanese study
with lab rats, cross fostered babies, some moms given non-lethal dose to induce immunity, antibodies from milk last longer than from in utero,
rats from seropositive dams are protected from hantavirus infection for extended periods after birth due to immune transfer from dams. (PDF)
- Protection against hantavirus infection by dam’s immunity
transferred vertically to neonates - K. Dohmae, Y. Nishimune. Archives of Virology, January 1995, Volume 140, Issue 1,
pp 165–172. Antibodies to hantavirus, Seoul type B-1 strain, were transferred to newborn rats from the moms and prevented
lethal as well as persistent infection.
- In utero and mammary transfer of hantavirus antibody from dams to infant rats -
Dohmae K, Koshimizu U, Nishimune Y. Lab Anim Sci. 1993 Dec;43(6):557–61. Cross-fostered experiments showed maternal antibody
was transferred either in utero or by breatfeeding and is protective against hantavirus infection for up to 15 weeks
- Role of maternal antibody in protection from hemorrhagic fever with
renal syndrome virus infection in rats - Zhang et. al., Archives of Virology, September 1988, Volume 103, Issue 3, pp
253–265. Protective effect of maternal antibodies remained up to 10 weeks in rats. (PDF)
- Effects Of Hantaviral Infection On Survival, Growth and Fertility In
Wild Rat (Rattus Norvegicus) Populations Of Baltimore, Maryland - James E. Childs, Gregory E. Glass, George W. Korch, and James
W. LeDuc. Journal of Wildlife Diseases, 25(4), 1989, pp. 469–476, Wildlife Disease Association (PDF)
- Antibodies from mom protect young rats for up to 10 weeks after birth;
some rats seroconverted from positive to negative, low antibody titers were presumed to be due to maternal antibody rather than to viral
infection; hantaviruses do not appear to influence the survival, size structure, or fertility of Norway rats. (PDF)
There are several research articles about Hantavirus being in various countries in Europe for many years and rats worldwide are
known to carry this virus. There are very few reports of human infections.
- Migration of Norway Rats Resulted in the Worldwide Distribution of Seoul
Hantavirus Today - Xian-Dan Lin, Wen-Ping Guo, Wen Wang, et al. J. Virol. January 2012 vol. 86 no. 2 972–981.
Researchers hypothesize Seoul hantavirus came from China, exported to Europe, then spread through the New World through the
migration of Norway rats; virus may have arisen in the last few centuries.
- Hantaviruses: a global disease problem - C. Schmaljohn
and B. Hjelle. Emerg Infect Dis. 1997 Apr-Jun; 3(2): 95–104. Infection not harmful to host; each hantavirus has
a single natural reservoir and do not adapt readily to new hosts; highest antibody in mature animals; not transferred from
dam to pup.
- Laboratory rat associated outbreak of haemorrhagic fever with renal
syndrome due to Hantaan-like virus in Belgium - Desmyter J, LeDuc JW, Johnson KM, Brasseur F, Deckers C, van Ypersele de
Strihou C. Lancet. 1983 Dec 24-31;2(8365-66):1445–8. First confirmed cases outside of East Asia of Hantaan-like
virus from lab rats found in Belgian university staff in 1983.
- Seoul hantavirus in Europe: first demonstration of the virus
genome in wild Rattus norvegicus captured in France - Heyman, P., Plyusnina, A., Berny, P. et al. European Journal of Clinical
Microbiology & Infectious Diseases. Sep 2004, Vol. 23 Issue 9, p711–717. Rats occasionally have been found to be antibody
positive though the viral genome has not been demonstrated in these animals.
- Pet rat harbouring Seoul hantavirus in Sweden,
June 2013 - Å Lundkvist, J Verner-Carlsson, A Plyusnina, L Forslund, R Feinstein, A Plyusnin. Eurosurveillance,
Volume 18, Issue 27, 04 July 2013. One rat imported to Sweden from England in 2011 (20 total imported and all being tested)
was found SEOV infected but found to not have a U.K. strain but rather a new strain that was most closely related to SEOV
strains from Indonesia and Belgium; unclear if the rat had been infected in the U.K., or later in Sweden; hantavirus species
have single reservoir host species.
- First evidence of Seoul hantavirus in the wild rat population in
the Netherlands - Jenny Verner-Carlsson, MSci, et al. Infect Ecol Epidemiol. 2015; 5: 10.3402/iee.v5.27215. Three out
of 16 wild rats caught and tested in 2013 were positive for Seoul hantavirus; rats tested during 2008–2011 were not confirmed
as having this; eradication unrealistic; SEOV only known hantavirus with a world-wide distribution due to the ubiquitous occurrence
of its reservoir hosts, the brown and the black rat.
IDEXX BioResearch, The Radil Advantage Program - uses Opti-Spot
sample strips for serology testing; 3-18-17 - IDEXX now offering reduced price for multiple numbers of rats to be tested for Hantavirus,
$9 each for 10 or more submitted at the same time; new code: Hantaan Virus Antibody-10 or More Specimens #38881 vet code
Zoologix - molecular diagnostic testing for animals, located in Chatsworth, CA (does
Seoul Hantavirus testing - $85 per sample for PCR test—fecal,
blood, swabs, etc.—discounts for 5 or more); will do custom panels for other assays
CA: Strain of Hantavirus Is Discovered in Roof Rat Common
to S. County: Health: Seoul variety of the disease carried by a rodent in Orange is rarely fatal, but caution is urged. - Los Angeles
Times, August 4, 1999. 1999 article about Seoul virus found in wild Rattus rattus (roof rat) in Orange County (Southern California),
believed to be the first in Southern California.
of Health Services: 2 cases of rare viral illness linked to ‘ratteries’ reported in Wisconsin - Jan. 19, 2017. Two people in Wisconsin
tested positive after purchasing rats from 2 IL ratteries.
Department of Public Health Reports Six Cases Of Viral Illness Linked To Ratteries - Jan. 23, 2017. Six people in Illinois tested
positive from exposure to 2 IL ratteries.
Virus Outbreak with Pet Rats - Feb. 3, 2017, news video on IllinoisHomepage.net
ci Living show with Dr. Julia Whittington and
2 pet rats telling about the Seoul virus outbreak and what good pets rats make.
IN: Seoul virus case confirmed in Indiana -
Outbreak News Today, Feb. 11, 2017. One person tested positive.
LA: Hantavirus Infections -
Louisiana Dept. of Health, Feb. 13, 2017. Includes info on Seoul virus.
virus illustrates need for unified health approach AgriNews, Feb 13, 2017. No reports of Seoul virus found in pet rat testing during
past several years according to a national veterinary diagnostic laboratory.
Seoul virus diagnosed in Utah County resident - Deseret News, Utah, February 14, 2017.
virus: Rat breeding facility in El Paso County linked to multi-state outbreak - The Denver Channel, Colorado, Feb. 16, 2017
MN: Pet rat owners nervous about
rat-to-human virus being investigated in Minnesota, 14 other states - Star Tribune, Minneapolis, MN, February 17, 2017. Illinois
breeder found positive, all rats killed; 2 out of 3 MN ratteries tested negative, 3rd had couple rats positive, rest of rats in quarantine
till no more test positive.
PA: Pennsylvania Breeding Facility Rat Tests
Positive For Seoul Virus - CBS Philly, Pennsylvania, February 17, 2017. Rat brought in from TN breeder tested positive, all rats
US/CANADA: Seoul virus – United States
of America and Canada - World Health Organization, Feb. 20, 2017. As of Feb. 10, a Canadian rat breeder under investigation that
exported rats to the United States and imported rats from affected U.S. facilities; as of Feb. 10 there are 3 confirmed human positive
cases in Ontario, Canada.
breeder concerned about euthanasia methods after Seoul Virus confirmed - Feb. 24, 2017, KOAA News 5 video clip and story about Colorado
rat breeder Linda Adams and one of her rats tested positive to the Seoul Hantavirus and now all rats are slated to be killed.
CANADA: Outbreak of rat virus
reaches region - March 3, 2017, The Record, Kitchener, Ontario, Canada. Kitchener rat breeder Carol Gamble found positive for
virus; rats being tested.
- Disease Control - How to safeguard your animals
- Quarantine, Quarantine, Quarantine: Ill Rat - by Carmen Jane Booth, D.V.M.
- Quarantining - by Karen Robbins & Carmen Jane Booth, D.V.M.
- Quarantining Part 2 - by Karen Robbins
- Places to check for Veterinarians:
Back to top