A Buddhist nun in the Central Highlands died of swine flu on Tuesday, bringing the total number of deaths caused by the disease this year to four.

The woman first began suffering from fever and fatigue before being taken in for a health check-up. On November 3, she was admitted to a general hospital in Kon Tum City for treatment, but died five days later. Results from her admission confirm she contracted swine flu, Tuoi Tre reports.

Following the death, 44 others who were in close contact with the woman have been placed in quarantine and given the antiviral medication Tamiflu. From tests, at least one has tested positive for the virus.

Swine flu is a respiratory disease that causes colds, sore throats, coughs, and fever, and is caused by the virus H1N1, originally found in pigs. The first outbreak among humans occurred in 2009, according to the World Health Organization. Last year, it killed eight people in Vietnam.

The disease is not to be confused with African swine fever which, as of September this year, had infected pigs in all 63 provinces and cities in Vietnam, a worrying development for the local animal husbandry industry. Ninh Thuan was the last province to be affected, according to VnExpress.

Vietnam is the sixth-largest pork producer globally, with a population of 30 million pigs and the industry supporting the livelihood of 2.4 million households. The protein also makes up 70% of the Vietnamese diet.