ALBANY COUNTY — This week, the Centers for Disease Control and Prevention changed its guidance on disinfecting surfaces to prevent COVID-19, reflecting what scientific studies have shown.

The principal way that people are infected with SARS-CoV-2, the virus that causes COVID-19, is through exposure to respiratory droplets carrying infectious virus, the CDC posted in a science brief on April 5.

It is possible for people to be infected through contact with contaminated surfaces or objects, called fomites, but the risk is generally considered to be low, the brief says.

“Findings of these studies suggest that the risk of SARS-CoV-2 infection via the fomite transmission route is low,” the brief says, “and generally less than 1 in 10,000, which means that each contact with a contaminated surface has less than a 1 in 10,000 chance of causing an infection.” 

The CDC also reports, “Data from surface survival studies indicate that a 99% reduction in infectious SARS-CoV-2 and other coronaviruses can be expected under typical indoor environmental conditions within 3 days (72 hours) on common non-porous surfaces like stainless steel, plastic, and glass.”

On porous surfaces, studies report inability to detect viable virus within minutes to hours.

When a person with suspected or confirmed COVID-19 has been indoors, virus can remain suspended in the air for minutes to hours, the brief says.

“The length of time virus remains suspended and is infectious depends on numerous factors,” the brief goes on, “including viral load in respiratory droplets or in small particles, disturbance of air and surfaces, ventilation, temperature, and humidity ... Wearing masks consistently and correctly can substantially reduce the amount of virus indoors, including the amount of virus that lands on surfaces.”

After 24 hours of entering a space where an infected person has been, the CDC says, there is little risk of contracting the disease.

This, in turn, changes the guidance, for example, for schools, which have been daily disinfecting surfaces. Surfaces now are to be disinfected only if someone who has COVID-19 has, say, been in a classroom or on a school bus.

“The principal mode by which people are infected with SARS-CoV-2 is through exposure to respiratory droplets carrying infectious virus. In most situations, cleaning surfaces using soap or detergent, and not disinfecting, is enough to reduce risk,” the CDC says.

The CDC notes in another April 5 post, on cleaning and disinfecting, “The effectiveness of alternative surface disinfection, such as ultrasonic waves, high intensity UV radiation, and LED blue light against the virus that causes COVID-19 has not been fully established.”

Disinfection is recommended in indoor community settings where there has been a suspected or confirmed case of COVID-19 within the last 24 hours.

“The risk of fomite transmission can be reduced by wearing masks consistently and correctly practicing hand hygiene, cleaning, and taking other measures to maintain healthy facilities,” says the CDC.

Albany County Executive Daniel McCoy in a release on Friday continued to stress the importance of following the protocols he has been pushing for more than a year: “Please continue to wear a mask, socially distance and cough and sneeze into your elbow,” he said.

McCoy noted, “We’re still seeing the virus spreading and people are still being hospitalized. The number of residents currently in the hospital has gone up from 21 to 30 over the last week.”

He stressed the importance of getting vaccinated. All New Yorkers age 16 and older are now eligible for vaccination.

As of Friday evening, 43.6 percent of Albany County’s 307,117 residents have received at least one does of vaccine, according to the state’s vaccine tracker. In his Friday morning release, McCoy said that 28.9 percent of county residents have been fully vaccinated.

Statewide, 36 percent of New Yorkers have received at least one dose while 23.1 percent have completed a vaccination series.

“As has been the case since the beginning of our vaccination effort, the X-factor is supply, supply, supply, and like every other state, our allocation of Johnson & Johnson doses will be significantly lower next week,” Governor Andrew Cuomo said in a release on Friday.

“In Week 18, New York will receive just 34,900 Johnson & Johnson shots — a drop of 88 percent week-over-week and the first decrease in weeks,” he went on. “While no appointments should have to be canceled, we will not be able to get as many shots into New Yorkers’ arms as we would like. We hope the production issues are resolved as soon as possible, and that production ramps up quickly so we can expand the number of New Yorkers who are vaccinated.”

Several weeks ago, workers at the Baltimore factory mixed ingredients from the coronavirus vaccines of Johnson & Johnson and AstraZeneca, contaminating up to 15 million doses of Johnson & Johnson vaccine and forcing regulators to delay authorization of the plant’s production lines, according to The New York Times; Johnson & Johnson doses that are currently being delivered and used in the United States were made in the Netherlands.

Newest numbers

McCoy reported 71 new cases of COVID-19 on Friday morning, bringing the county’s tally to 22,848.

Of the new cases, 38 did not have clear sources of infection identified, 26 had close contact with someone infected with the disease, five were health-care workers or residents of congregate living settings, and two reported traveling out of state.

The five-day average for new daily positives has increased to 60.8 from 58.8. There are now 520 active cases in the county, up from 511 on Thursday.

The number of Albany County residents under quarantine dropped to 1,209 from 1,248. So far, 73,254 residents have completed quarantine. Of those, 22,328 had tested positive and recovered. That is an increase of 59 recoveries since Thursday.

There were three new hospitalizations overnight and there are now 30 county residents hospitalized from the virus — a net increase of four. There are currently seven patients in intensive-care units, unchanged from Thursday.

Albany County’s COVID-19 death toll remains at 366.

Albany County’s infection rate, as of Thursday, as a seven-day rolling average, was 2.3 percent, according to the state’s dashboard.

Statewide, also as of Thursday, as a seven-day rolling average, the infection rate was 3.4 percent.