WHO: hantavirus cases rise to 12

The World Health Organization said on May 22 that a crew member from the cruise ship MV Hondius tested positive for hantavirus in the Netherlands, bringing the total number of reported cases linked to the vessel to 12. Dutch health authorities said the patient had been in home quarantine after close contact with infected people on board and was later admitted to a hospital in isolation. Three deaths have been reported in the outbreak, and no new deaths have been reported since May 2, WHO Director-General Tedros Adhanom Ghebreyesus said. WHO and national agencies are still tracing contacts across multiple countries as passengers and crew complete quarantine and monitoring periods. ### Why did one new crew case change the story? Friday's confirmation matters because earlier WHO and Dutch updates had centered on infected passengers, while tests on crew members arriving in Rotterdam on May 18 had initially come back negative. The new positive case showed that monitoring was still catching infections after disembarkation and quarantine had begun. Dutch public health agency RIVM said weekly testing identified the infection early and that the patient was hospitalized as a precaution. (nbcnews.com) Tedros said the crew member had disembarked in Tenerife and was repatriated to the Netherlands, where the person had been in isolation. He said the incubation period for hantavirus can run up to six weeks and urged affected countries to keep monitoring passengers and crew for the rest of the quarantine period. (rivm.nl) ### What virus are investigators dealing with on this ship? WHO said laboratory-confirmed cases from the cluster have been identified as Andes virus, a hantavirus strain tied to severe respiratory disease. The agency said eight cases had been laboratory-confirmed as of May 13, with two probable cases and one inconclusive result at that point; the new Dutch crew case later pushed the total to 12. WHO said its working hypothesis is that the first case was infected before boarding the ship, with investigators examining possible exposure on land in coordination with authorities in Argentina and Chile. (nbcnews.com) The U.S. Centers for Disease Control and Prevention said on May 8 that the risk of broad spread in the United States was considered extremely unlikely. CDC said the ship had departed Ushuaia, Argentina, on April 1 and carried 147 people from 23 countries during an itinerary that included Antarctica and remote South Atlantic stops. ### How many people are still being tracked? (who.int) Tedros said more than 600 contacts in 30 countries are still being followed, and that a small number of high-risk contacts were still being located. WHO said national focal points under the International Health Regulations had been informed and were supporting international contact tracing efforts. (cdc.gov) RIVM said the risk of spread in the Netherlands remains very small and that strict precautions were taken during the outbreak on the ship and during transfers to the Netherlands. The agency said people considered at risk were placed into quarantine immediately on arrival and are being monitored by local public health services. ### What is happening with U.S. passengers? (nbcnews.com) On May 19, CDC said 18 repatriated U.S. passengers had been asked to remain at the Nebraska Quarantine Facility through May 31, which it said would mark day 21 of their monitoring period. CDC said two passengers in Nebraska were under federal quarantine orders and that additional post-disembarkation cases had been identified in France, Spain and Canada. (rivm.nl) CDC said earlier that it had sent a team to meet the ship in Spain and was coordinating with federal, state, local and international partners on repatriation and monitoring. The agency said clinicians should be alert to imported cases, even though the public-health risk in the United States remained extremely low. ### What comes next as the quarantine period runs on? (cdc.gov) May 31 is the next dated milestone in the U.S. response, when CDC says the Nebraska monitoring period for 18 passengers is due to reach 21 days. In the Netherlands, RIVM said it would publish further updates if additional positive test results are found, while WHO said countries should continue monitoring passengers and crew through the remainder of the quarantine period. (cdc.gov 1) (cdc.gov 2)