An outbreak of Hepatitis A in Michigan that began in August 2016 has seen the number of cases reported in 2017 increase by a factor of ten since 2015, the last full year of reporting prior to the current outbreak.
According to the Michigan Department of Health, 553 cases of Hepatitis A have been reported in Southeast Michigan alone in 2017, compared to only 51 in the entire state in 2015.
The Centers for Disease Control (CDC) reported that there were 1,390 cases of Hepatitis A in the United States in 2015, or 0.4 per 100,000 residents of the United States.
Michigan reported 51 cases of Hepatitis A that year, enough to put it in the top ten states, but well behind California, which reported 179 cases; Texas, which reported 143 cases; and New York, which reported 123 cases.
This year, which still has two more weeks to go, is an entirely different matter, with Michigan already reporting more than 500 cases of Hepatitis A, according to the Detroit Free Press, ten times more than the number of cases reported in the state in 2015.
Disease Daily reported last week:
Hepatitis A is an infection caused by the Hepatitis A virus, and is typically transmitted through the fecal-oral route or consuming contaminated food or water. Symptoms of the infection include fatigue, lack of appetite, nausea, diarrhea and jaundice; symptoms can last up to two months after the initial infection. Hepatitis A is a vaccine-preventable disease. These outbreaks have been severe, with over 80% of cases requiring hospitalization.
“The specific strain of Hepatitis A virus (genotype IB) is not commonly seen in the U.S., but is rather common in the Mediterranean, Turkey and South Africa. The initial source of the outbreaks among these states is unknown, but several states have linked cases serologically,” Disease Daily noted. (emphasis added)
“An alarming number of hepatitis A cases have swept across southeast Michigan since August 2016 in what public health officials said is one of the largest outbreaks to occur in the United States since a vaccine was widely introduced two decades ago. In 2017 alone, Michigan has led the nation in hepatitis cases per capita, according to a Free Press analysis. More than 500 cases have been reported this year.” the Detroit Free Press reported last week:
Detroit and Macomb County have the highest rate of outbreak related cases at about 2 cases per 10,000 residents.
The cause of the outbreak is not yet known but officials say they’re probing a link to the ongoing opioid and heroin crisis seen across Michigan, as well as other potential exposure routes.
“We’re continuing to see new cases almost every day so it is a concern,” said Macomb County Health Department Director Bill Ridella. “I think there is a strong connection to a number of these cases with the opioid and heroin problem. About half of the cases in Macomb County has some connection with drug use and/or heroin.”
But state officials said since other exposure routes have been found, it hasn’t been easy to discern the exact origin.
“Typically what we would see this time of year is about 14 times lower than what we’re currently dealing with,” said Angela Minicuci, Michigan Department of Health and Human Services spokesperson. “I don’t know if we’ve seen a hepatitis A outbreak like this before.”
“In 2017, several states have experienced acute outbreaks of Hepatitis A, namely Michigan, Kentucky, Utah, Colorado, and California. Each state varies in regards to outbreak onset and population affected, but one similarity has emerged among these states where those experiencing homeless and people who inject drugs (PWID) have been the largely affected population,” Disease Daily reported last week.
In these five states alone, 1,430 cases of Hepatitis A have been reported so far in 2017, more than the 1,390 cases that were reported in the entire United States in 2015. Data on rates of Hepatitis A in the rest of the United States for 2017 is not yet available.
Disease Daily reported that Michigan has experienced the greatest increase in the number of reported cases of Hepatitis A over the past year and a half:
Michigan began to see an unexpected number of Hepatitis A cases since August of 2016, and the outbreak has continued to present day. Almost 600 cases have been recorded, including 20 deaths. This outbreak is nearly 10 times the amount of cases typically seen over this time period. No link to common sources of food or beverages has been found between cases, but a pattern has emerged where homeless people and PWID are at greatest risk for infection.
Disease Daily noted that Hepatitis A rates are also up significantly in Kentucky, Utah, Colorado, and California:
As of late November, 31 cases of Hepatitis A have been reported in Kentucky, a 50% increase from the average annual number of cases seen in the past decade. No deaths have occurred due to this outbreak. 19 of the 31 cases have come from Jefferson County, which contains the city Louisville, and have also shown a pattern of homelessness and IV drug use among cases.
Since the beginning of 2017, Utah has reported 112 confirmed cases of Hepatitis A, 102 of which are associated with the current outbreak. The areas affected in this outbreak have reported around a 70% hospitalization rate for cases; however, no deaths have been reported. Again, the populations largely affected in this outbreak are those experiencing homelessness and PWID.
The outbreak in Colorado has reached double the number of expected cases in 2017, with a total reported case count of 62, and one death. Fifteen counties in total have been affected, with the greatest number of cases coming from the Denver and El Paso counties. Many of the Colorado cases have occurred among men who have sex with men (MSM) and homeless individuals, and two cases have been linked to the outbreak in California.
San Diego, Santa Cruz, and Los Angeles counties have reported an outbreak of Hepatitis A within California. Within these three counties, there has been a total of 672 cases reported, 430 hospitalizations (64.0% hospitalization rate), and 21 deaths. The California Department of Public Health reported that the majority of patients in this outbreak are experiencingare homeless ness or IV drug users. The outbreak in California is the largest Hepatitis A outbreak in the U.S. since the introduction of the vaccine in 1996.
The Hepatitis A virus infection is easily preventable through vaccination, however,though many adults remain unvaccinated as the vaccine was introduced in 1996. As of 2016, the reported rate of hepatitis A vaccination among adults aged 19 or greater was just 9.0%. It is possible for the vaccine to be effective after exposure to the virus, if administered within 2 weeks of the exposure. Due to the current outbreak, there has been a large increase in demand for the vaccine in order to prevent further transmission. However, this has caused a shortage of the Hepatitis A vaccine, leaving it difficult for public health departments to combat the outbreak effectively. The Centers for Disease Control and Prevention are supporting efforts to increase vaccine supply and vaccine policy development. Education campaigns regarding proper sanitation, Iin addition to vaccination, education campaigns regarding proper sanitation are being used to put an end to the outbreak that is now affecting several U.S. states.
“San Diego’s ongoing hepatitis A outbreak has now killed 20 people in San Diego and, with the number of cases still on the rise, concern continues that the health emergency could reach new populations,” the San Diego Union-Tribune reported in October:
The county Health and Human Services Agency published new weekly totals Tuesday, which add one to the number of deaths recorded since the health crisis started in November 2016. The running tally of confirmed cases also continues to increase, reaching 536 from a previous total of 516.
Dr. Eric McDonald, chief of the county’s Epidemiology and Immunization Services Branch, said that the latest fatal case was a 67-year-old man who died on Oct. 26.
The man, McDonald said, was previously infected with hepatitis A but seemed to recover before symptoms returned. Like most of those who have died during the outbreak, the man had underlying liver problems. It was not clear Tuesday if he was homeless or an illicit drug user, the two populations most affected by the disease along with those who have contact with them.
Since “The specific strain of Hepatitis A virus (genotype IB) [in the 2016-2017 outbreak] is not commonly seen in the U.S., but is rather common in the Mediterranean, Turkey and South Africa,” as Disease Daily reported, the current outbreak may have originated abroad.
Although no study appears to be currently in process to explore a possible causal relationship between the current Hepatitis A outbreak and immigration or foreign travel, common sense suggests it is an area worthy of research.
It is worth noting, for an instance, a recent study published in Eurosurveillance, “Europe’s journal on infectious disease epidemiology” this year, which found that:
An increased number of hepatitis A cases among refugees, asylum seekers and migrants residing in hosting facilities in Greece were recorded between April and December 2016.
In total, 177 laboratory-confirmed symptomatic cases were reported; of these, 149 (84%) occurred in hosting camps mostly among Syrian children under 15 years. All cases reported symptom onset after their entry into the country. Public health interventions focused on hygiene measures and vaccination.
Refugees accepted for admission into the United States are not tested for Hepatitis A, according to the CDC.
Between January 1, 2016, and November 30, 2017, 18,503 refugees from Syria have been admitted into the United States. California and Michigan were the top two destinations for these Syrian refugees during this period, with a total of 2,019 resettled in California, and 1,986 resettled in Michigan, according to the State Department’s interactive website.