ILLUSTRATION of Hantavirus testing concept with laboratory tubes containing cotton swabs and HANTAVIRUS labels photographed in front of a public domain microscopic image related to Hantavirus released by the US Centers for Disease Control and Prevention in Paris, France on May 8, 2026.
João Luiz Bulcao | Afp | Getty Images
A hantavirus outbreak caused a brief rise in shares of companies working to develop a vaccine, but the stocks were unable to maintain their initial gains.
THE World Health Organization reported an outbreak of hantavirus, a deadly viral respiratory disease transmitted by rodents, on May 2 after some passengers caught it on a Dutch-flagged expedition cruise ship, the MV Hondius, which was sailing the Atlantic.
The public health risk from the virus is low, according to the WHO and other health authorities who have noted human transmission is rare.
Which pharmaceutical and biotechnology stocks are on the rise?Biotechnology company Modernwhich developed one of the leading Covid-19 vaccines, rose less than 1% after saying it was conducting preclinical research on the virus. Shares had hit a high of $59.48 earlier in the session.
“Moderna has conducted preclinical research on hantaviruses in collaboration with the U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID), reflecting the current regional impact of these pathogens,” he said in a statement shared with CNBC.
“These efforts are early and ongoing and reflect Moderna’s broader responsibility to develop countermeasures against emerging infectious diseases.”
Evercore ISI said last week that it was unlikely to be a revenue opportunity for Moderna in the case of hantavirus.
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Moderna stocks since the start of the year compared to several other pharmaceutical stocks.
“As a name with significant retail traffic, [Moderna] tends to trade on outbreak headlines well beyond the underlying business implications,” Evercore analysts said in the note published May 7. “As for current headlines, we do not see any significant revenue opportunities.”
“Hantavirus is a low-incidence and structurally small market, and we view any potential outsized moves as sentiment-driven and not fundamental. At most, it enhances the agility of Moderna’s mRNA platform, something already well understood post-COVID,” they added.
Meanwhile, a vaccine development company Inovio Pharmaceuticals fell 1%, while biotech companies Novavax And Emerging BioSolutions each fell 5% and 1%, respectively. All three stocks posted gains in early trading.
US President Donald Trump said the cruise ship outbreak was under control and a report on the virus would follow soon.
“It is, we hope, very much under control,” Trump told reporters Thursday. “It was the ship, and I think we’re going to do a full report on it tomorrow. We have a lot of people. … It should be fine.”
What is hantavirus and how serious is the epidemic?The hantavirus strain in this case is the Andes virus, which is the only species capable of causing human-to-human transmission, according to the WHO.
WHO Director-General, Tedros Adhanom Ghebreyesus said Friday that eight cases have been reported so far, with three deaths, and five of the cases confirmed as hantavirus. THE The WHO assessed “the risk to public health as low,” Ghebreyesus said.
The MV Hondius now has moored in Tenerife in the Spanish Canary Islands, after spending several days offshore while awaiting authorization.
Passengers and crew began disembarking under strict health protocols, with authorities coordinating testing, isolation and repatriation efforts in several countries while continuing to monitor the spread of the virus.