Hepatitis A is a vaccine-preventable liver infection. The virus spreads when someone swallows food or drink contaminated with tiny amounts of an infected person's stool, or through close contact — including sex — with someone who has it. After years of historically low rates, U.S. cases began rising in 2016, in outbreaks spreading person to person among people who use drugs, people experiencing homelessness and men who have sex with men. By September 2022, 13 states — Virginia among them — had outbreaks.
The restaurant outbreak, 2021
The Roanoke City and Alleghany Health Districts, serving about 280,000 people in southwestern Virginia, had seen only six hepatitis A cases in 2019–2020 and none through August 2021. Then, in mid-September 2021, five were reported in a single week.
| Common source | a local restaurant chain |
| Index patient | an unvaccinated food handler with risk factors for hepatitis A, who had worked at three of the chain's locations — waited more than two weeks after falling ill to seek care, and at first didn't mention the job |
| How it spread | inspectors found the worker had handled ready-to-eat food with bare hands while infectious |
| Diners at risk | anyone who ate at the three restaurants from August 10 to 26, 2021 |
| Result | by the investigation's close on November 20, 2021: 51 cases, 31 hospitalizations and 3 deaths; patients' median age 64 |
The first press release, on September 24, 2021, urged anyone with symptoms to see a doctor. Because the exposures were already outside the two-week window in which a vaccine or immune globulin can prevent infection after exposure, that was not offered to the public. The health districts offered vaccination — even on site — to the restaurants' employees and patients' close contacts, but fewer than 20% of eligible employees took it.
Why so severe? With hepatitis A's long incubation — 15 to 50 days — the worker's delay in seeking care, and the undisclosed job, the virus had spread widely before the source was found. The patients' older age and other illnesses likely made outcomes worse.
A year of community spread
From October 2021, cases appeared that had no direct link to the restaurants — 13 more by the end of 2021 and 98 in all by September 30, 2022, with 64 hospitalizations. The same genotype IB sequence was found in 8 of 9 restaurant specimens and in all 5 community specimens sequenced, but a direct link couldn't be proved: that genotype isn't rare, and only 40 of the 98 community patients could be interviewed (57 had too little contact information; one refused).
| Restaurant cases (51) | Community cases (98) | |
|---|---|---|
| Median age | 64 | 40 |
| Hospitalized | 31 (60.8%) | 64 (65.3%) |
| Died | 3 | 0 |
| Liver transplant | 1 | 0 |
| Jaundice | 52.9% | 54.1% |
| Dark urine | 70.6% | 33.7% |
| Fatigue or malaise | 86.3% | 37.8% |
| Nausea | 74.5% | 55.1% |
| Diabetes reported | 21.6% | 4.1% |
Among the community cases, the commonest risk factors were drug use (85.7%, including injection drug use, 74.5%) and homelessness (12.2%).
Hepatitis A cases by week, restaurant-associated and community, September 2021–September 2022. CDC
The response and the cost
In 2022, three more cases were found in local restaurant workers, and the same steps followed. The health districts also teamed up with community organizations to teach people about hepatitis A and bring vaccine to those at risk — more than 2,500 doses by September 30, 2022.
The outbreaks cost more than $3 million in direct costs alone — hospitalizations at $16,232 each, a liver transplant at $1,427,805, and vaccine — not counting staff time or patients' lost wages.
Reaching people at risk
Hepatitis A vaccine is safe and effective and has been part of the routine childhood schedule since 2006. For adults, it is recommended for anyone who asks for it and for groups at higher risk: people who use drugs, men who have sex with men, people experiencing homelessness, and international travelers. Yet in 2011–2016, about two thirds of U.S. adults who injected drugs (67%) and of men who have sex with men (64%) said they had not been vaccinated.
People who use drugs can be hard to reach — behavioral health problems, little contact with health care, lack of transportation. A 2013 SAMHSA study found the restaurant industry had the highest rate of drug use of any industry, with nearly 20% of food service workers reporting use in the previous month; with 15.3 million people working in food service in 2019, that suggests nearly 3 million workers might use drugs. The authors suggest health departments partner with employers such as restaurants: workers who wouldn't disclose a risk factor might accept vaccination their employer encourages — and it avoids stigmatizing them.
Limits
- The outbreaks overlapped the COVID-19 Delta and Omicron surges, which may have led to under-reporting.
- Heavy media coverage may have increased testing and found unrelated cases.
- Many patients couldn't be interviewed, so risk factors and links may be under-reported.
- Because genotype IB is common, the restaurant outbreak can't be proved to have caused the community spread.
Sources
Based on Helmick MJ, Morrow CB, White JH, Bordwine P, "Widespread Community Transmission of Hepatitis A Virus Following an Outbreak at a Local Restaurant — Virginia, September 2021–September 2022," MMWR Morbidity and Mortality Weekly Report volume 72, number 14, Centers for Disease Control and Prevention; a work of the United States government in the public domain.
许可协议： CC0 1.0（公有领域） · 改编自 www.cdc.gov
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