The Nipah virus outbreak in India, previously covered by Outbreak Observatory, has been declared over by India’s health officials. The outbreak resulted in 18 confirmed cases and 16 deaths (plus the suspected index case, who died without being tested) in the state of Kerala, but the impact of this outbreak reaches beyond morbidity and mortality. This week, Outbreak Thursday looks at the effects of this outbreak on the economy of the Indian state of Kerala, as well as at other infectious disease outbreaks that have threatened economic stability as a result of other countries' actions.

Nipah in Kerala

Nipah virus, which can quickly progress from fever to severe respiratory distress and encephalitis, has been contained in India. Kerala’s Minister for Health and Social Justice announced on June 10 that the final case had recovered and that emergency had ended. The state will enter a monitoring period through June 30. The government also announced that schools in the region would re-open and that a ban on public gatherings would be lifted.

Although fears of continued spread of Nipah in Kerala may be declining, multiple trade bans loom over the state’s fruit exports. The WHO acknowledges that one of the means of transmission in past outbreaks most likely was fruit infected by bats. It recommends that people wash and peel fruits during outbreaks and discard fruits that appear to have been eaten by bats. Based on this information, several Middle Eastern countries—including Saudi Arabia, Bahrain, Qatar, and the United Arab Emirates (UAE)—announced that they would cease importation of fruits and vegetables from Kerala. According to a statement in late May by the All Kerala Fruit Merchants Association, mangoes were rotting in trucks and mango sales dropped by 75%. Rather than seeing the typical surge in fruit and vegetable sales expected during Ramadan, Kerala fruit sales actually dropped during the Muslim holy month. In fact, sales were 25% of normal months and 12.5% of what was expected for Ramadan. Several countries—including Bahrain, Qatar, and UAE—also recommended that their citizens avoid or delay travel to the area. [NOTE: UAE lifted its travel advisory on June 19.]

Prior Economically Damaging Outbreaks

We have seen similar international measures take place during prior outbreaks. The 1998-99 outbreak of Nipah virus in Malaysia, for example, was initially attributed to mosquitoes; however, when it was discovered that the virus was transmitted by pigs, Malaysia implemented a massive, two-phase operation to cull pigs at affected farms. Ultimately, more than a million pigs were culled over a period of several months. Additionally, the Philippines, Singapore, and Thailand all banned the import of Malaysian pork. According to a FAO report, the initial Nipah outbreak cost the Malaysian government US$35 million directly in compensation to farmers for the culled pigs, US$105 million in tax revenue, and an additional US$120 million in pork exports. Singapore finally lifted the ban on imports of raw Malaysian pork in 2015, 16 years after the initial outbreak, and it took another 2 years to lift the ban on the import of live Malaysian pigs. In another example, Switzerland banned Hong Kong businesses from participating in a high-profile watch and jewelry show in the midst of the SARS pandemic in 2003, resulting in millions of dollars (HK) in losses due to cancelled travel arrangements and untold millions in potential business. The ban resulted in multiple lawsuits, involving the Hong Kong Trade Development Council, Swiss health officials, and the event organizers.

The International Health Regulations (2005)

The WHO’s International Health Regulations (2005) were established to ensure that the countries do not take actions that cause “unnecessary interference with international traffic and trade.” Based on the available evidence, the WHO advised against countries implementing travel or trade restrictions in response to the Nipah outbreak in India. In light of this determination, bans on importing fruits and vegetables from Kerala and the advisories recommending against travel to the area could be in violation of the International Health Regulations. These types of measures not only do not contribute to control of the outbreak, they may actively cause further damage to the affected country and population (eg, economic losses). Furthermore, they may discourage countries from reporting future outbreaks over concern that they may face similar responses.


The economic effects of infectious disease outbreaks are well documented, and this most recent Nipah virus outbreak is no exception. Although it appears that the fight to contain the virus is over, the effects of the outbreak will be felt as long as trade and travel restrictions remain in place.


Photo is a transmission electron microscope (TEM) image of Nipah virus virions isolated from a patient's cerebrospinal fluid (CSF); courtesy of CDC/Cynthia Goldsmith

Outbreak Observatory aims to collect information on challenges and solutions associated with outbreak response and share it broadly to allow others to learn from these experiences in order to improve global outbreak response capabilities.