By NANCY WEST, InDepthNH.org
MANCHESTER – A new state report confirmed that norovirus caused the outbreak that sickened 19 people and contributed to the death of one man after an event at the Puritan Backroom Convention Center, but said it couldn’t determine how it originated or how it was transmitted.
However, the report didn’t rule out the possibility that food was the source or the possibility that an ill attendee or ill food service worker introduced norovirus to the event.
The highly contagious virus is usually transmitted through contaminated food, water, person-to person contact with an infected person, or by touching a contaminated surface and putting unwashed hands in one’s mouth, according to the report released Thursday by the state Division of Public Health, Bureau of Infectious Disease Control, Infectious Disease Surveillance Section.
The state was unable to determine the source of this norovirus outbreak because none of the evidence pointed to any of the usual transmission mechanisms or identified a common source.
“As a result, this norovirus outbreak is classified as being of indeterminate origin,” the report said.
The Puritan is partially owned by U.S. Rep. Chris Pappas, D-N.H., who has not commented about the outbreak, but has said he stepped away from the popular business when he was elected.
Attempts to reach other owners Thursday were unsuccessful. The state Department of Health and Human Services didn’t respond to a request for further information and Philip J. Alexakos, chief operations officer at the Manchester Health Department referred all questions to the DHHS.
No food items were identified that increased the risk of developing illness, but that does not exclude the possibility that food was the source of the outbreak, according to the eight-page report.
“It is possible that multiple food items were contaminated or that a particular food item had lower levels of contamination, which could limit the ability of the investigation to identify a single common implicated food item,” the report said.
The report also said low statistical power, the small numbers due to the group’s size, may also impact the ability of an investigation to identify a statistically significant food item.
“There were also no food service workers who reported illness at the time of the event,” according to the report. Two reported becoming sick after the event.
Also, none of the attendees reported illness in the seven days prior to or at the time of the meal. The day after the event was the first day any of the attendees started feeling ill.
The report provided the caveat: “However, the investigation relied on the information that people are able to recall and willing to share and the possibility that an ill attendee or ill food service worker introduced norovirus to the event cannot be excluded.”
The full report can be read here: http://indepthnh.org/wp-content/uploads/2020/01/norovirus-outbreak-2019-3.pdf
“Most items, including the Greek salad, pasta salad, chicken tenders, macaroni and cheese, mashed potatoes, and green beans were prepared by staff the day-of the event in large batches that were served to restaurant patrons as well as other event groups,” the report said.
And there were no reports of illness made to the Puritan Backroom, Manchester Health Department or the Department of Health and Human Services from other groups using the conference center or restaurant on the day of the event.
The Manchester Health Department environmental assessment began on Nov. 27, 2019, three days after the event in which a group of 40 family and friends ages 2 to 62 gathered at the Puritan.
The state Bureau of Infectious Disease Control, Infectious Disease Surveillance Section, was first notified on Nov. 27, 2019, by the chief medical examiner’s office that a person died after becoming ill with an unspecified gastrointestinal illness following a group meal at the Puritan, the report said.
On the day of notification, the state contacted the Manchester Health Department to request an immediate environmental assessment at the Puritan Backroom and launched an investigation into the possible outbreak among meal attendees.
The report also provided general information about norovirus:
Norovirus is a very contagious virus that causes vomiting and diarrhea. The virus is shed in the vomit and stool of people who are sick and is spread by having direct contact with an infected person, from eating or drinking contaminated food or water, or touching contaminated surfaces and then putting unwashed hands in the mouth.
There is no specific treatment for norovirus and most people with norovirus illness get better within 1 to 3 days.
Each year, on average, norovirus causes 19 to 21 million infections in the United States and it contributes to about 570 to 800 deaths, mostly among young children and the elderly.
Norovirus is not a reportable disease in New Hampshire, meaning individual cases of illness are not required to be reported to DHHS. As a result, it is not known exactly how many people become ill with norovirus in New Hampshire. However, outbreaks are required to be reported in New Hampshire and typically there are an average of 50 to 75 outbreaks each year of acute gastroenteritis, most due to norovirus (DHHS, unpublished data).