Influenza-like illness

Flu is rising in the Northeast, though it remains lower than in the South and West. Even so, activity is running well ahead of last season’s pacing. Hospital admissions are already at a level the region didn’t reach last year until late November.

I want to call out one nuance in this week’s data. Outpatient visits for influenza-like illness jumped, with children ages 0-4 making up a bigger share of those visits, but emergency department visits for flu stayed flat. That pattern sometimes suggests that other respiratory viruses are contributing to the outpatient numbers, since that metric relies on symptoms (fever and cough or sore throat) instead of a diagnostic test. For instance, New Jersey, which has the highest rate of flu-like illness in the region, and it also reports elevated parainfluenza and rhinovirus/enterovirus activity.

Bottom line though, the Northeast has a bit more time before flu season kicks in fully.

COVID-19

The Northeast is the only region where Covid-19 still leads flu in both emergency department visits and hospital admissions. Even so, Covid-19 activity is generally steady or declining. Wastewater levels fell from moderate to low this week, and hospital admissions are well below where in October of last year.

This is the time of year when Covid-19 stays elevated compared to the off season; activity never fully declines coming out of the summer season. Indicators may bounce around (up and down) through autumn months before increasing to a second peak around the turn of the new year.

RSV and other respiratory pathogens

RSV activity is very low across most of the Northeast. Wastewater concentration is very low everywhere except New Hampshire, where it is low, and RSV accounts for close to 0% of ED visits throughout the region. Hospital admissions are at or below 0.1 per 100,000 in New Hampshire, Connecticut, Maine, Massachusetts, Rhode Island and Vermont. CDC estimates that RSV activity is growing across most of the Northeast, so the weeks ahead will probably bring more activity.

Stomach Bugs

Norovirus test positivity increased to 7.1% from 6.0% the week prior, but levels are modest overall. Rotavirus activity is very low.

In Other News

Health officials in two upstate New York counties say the state’s measles outbreak is larger than reported counts reflect. The state has confirmed 126 cases so far, but contact tracers are learning that family members have recently recovered from a similar rash. On October 5, Governor Hochul declared a disaster emergency that allows paramedics, pharmacists and midwives to give measles vaccines and lets nurses order measles tests.

Pennsylvania has reported 1,260 measles cases this year, including 121 in the past week. So far, 238 people have been hospitalized and the state has reported six measles-associated deaths. Fewer than 1% of cases were fully vaccinated. The CDC said it will send experts to help Pennsylvania control the outbreak. Nationwide, 4,410 cases had been reported as of October 15.

State by State

Connecticut

Flu: Low. Outpatient influenza-like illness is 1.6%, and emergency department visits ticked up to 0.3%. Hospital admissions dipped to 0.5 per 100,000, and wastewater concentration is very low.

Covid-19: Highest Covid-19 wastewater level in the Northeast, though it dipped within the high range this week. ED visits are flat at 0.5%, among the highest in the region, and hospital admissions decreased from 1.8 to 1.5 per 100,000.

RSV: Very low.

Maine

Flu: Low. Outpatient influenza-like illness rose from 0.7% to 0.9%, and ED visits are flat at 0.4%. Hospital admissions ticked up to 1.1 per 100,000, among the highest in the Northeast. Wastewater concentration is very low.

Covid-19: Low. Wastewater concentration is low, and ED visits are about 0.3%. Hospital admissions ticked up to 0.3 per 100,000, or four patients, still the lowest rate in the Northeast.

RSV: Very low.

Massachusetts

Flu: Low but ticking up. Outpatient influenza-like illness rose from 1.4% to 1.7%, ED visits increased to 0.4%, and hospital admissions rose from 0.3 to 0.5 per 100,000. Wastewater concentration fell from low to very low.

Covid-19: Receding. Wastewater concentration fell from high to moderate, and ED visits dipped to 0.4%. Hospital admissions ticked up to 0.9 per 100,000.

RSV: Very low.

New Hampshire

Flu: Very low. Outpatient influenza-like illness dipped to 0.8%, the lowest in the Northeast, and ED visits are flat at 0.4%. Hospital admissions fell from 0.9 to 0.4 per 100,000, though NH’s small population makes some data unstable. Wastewater concentration is very low.

Covid-19: Wastewater concentration rose from very low to low, but ED visits fell from 0.5% to 0.3%, and hospital admissions dropped from 0.9 to 0.5 per 100,000.

RSV: Very low, though wastewater concentration is low.

New Jersey

Flu: Highest outpatient influenza-like illness in the Northeast at 3.2% but stable from last week to this one. Its other flu indicators are lower: ED visits are about 0.4%, hospital admissions are flat at 0.8 per 100,000, and wastewater concentration is very low. Test positivity is elevated for parainfluenza and rhinovirus/enterovirus, which may explain some of the state’s high rate of doctor visits for flu-like illness, according to the New Jersey Department of Health. Flu hospitalizations continue to be mainly among adults 65 and older.

Covid-19: Highest Covid-19 hospital admission rate in the Northeast, flat at 1.8 per 100,000, and about half of those patients were adults 75 and older. Wastewater concentration rose from low to moderate, while ED visits dipped to 0.5%.

RSV: A bit higher than most of the region, at 0.2 per 100,000. Admissions rose from 13 to 20, and 15 of those patients were children under 5.

New York

Flu: Outpatient influenza-like illness rose from 1.5% to 2.0%, but other flu indicators remain low. ED visits ticked up to 0.3%, hospital admissions are about 0.8 per 100,000, and wastewater concentration is very low.

Covid-19: Easing. Hospital admissions decreased from 1.8 to 1.6 per 100,000, ED visits dipped to 0.4%, and wastewater concentration is very low, the lowest in the Northeast.

RSV: A bit higher than most of the region, at 0.2 per 100,000. Of hospitalized patients, most were under age 5.

Pennsylvania

Flu: Low by most measures. Outpatient influenza-like illness ticked up to 1.3%, ED visits rose slightly to 0.3%, and wastewater concentration is very low. The state reported flu hospital admissions of 1.8 per 100,000, the highest in the Northeast, but Pennsylvania’s reported flu admissions have run unusually high all year, even through the summer, so they should be interpreted cautiously.

Covid-19: Wastewater concentration rose from very low to low. ED visits are flat at 0.2%, among the lowest in the region, and hospital admissions ticked up to 1.2 per 100,000.

RSV: Highest rate in the region, at 0.3 per 100,000, but unlike its neighbors, its highest rate is among adults 75 and older rather than young children. I’m wondering whether this is a reporting error or quirk.

Rhode Island

Flu: Very low. Outpatient influenza-like illness dipped to 1.3%, and ED visits are 0.2%, among the lowest in the Northeast. Hospital admissions fell to 0.3 per 100,000, or three patients. Wastewater concentration is very low.

Covid-19: Wastewater concentration jumped from very low to moderate. Hospital admissions decreased from 1.7 to 1.5 per 100,000, and ED visits are about 0.4%.

RSV: Very low.

Vermont

Flu: Wastewater concentration rose from very low to low. Hospital admissions jumped from 0.3 to 1.1 per 100,000, though that reflects only seven patients. Outpatient influenza-like illness is 1.0%, and ED visits ticked up to 0.2%.

Covid-19: Very low. Wastewater concentration fell from low to very low, and ED visits dropped from 0.3% to 0.1%. Hospital admissions rose to 0.5 per 100,000, but that reflects only three patients.

RSV: Very low.