Covid-19 rates are rising again: What you need to know

With the holiday season and colder winter months looming in the northern hemisphere, 'tis the season for Covid. But then again, Covid never really left us.

"The holiday season, marked by significant volumes of travel, is likely to be an additional determinant of transmission of Covid-19," said Rajib Dasgupta, an epidemiologist at Jawaharlal Nehru University, India.

The main variant of concern is now JN.1, a subvariant of Omicron -- one of the most prevalent forms of SARS-CoV-2, the virus that causes Covid.

Rates of JN.1 are increasing in many countries around the world. But the overall risk to the public is assessed as low, while existing vaccines continue to offer protection. That's the line from the World Health Organization (WHO) at time of publication.

Where are Covid-19 rates rising?

Germany has seen an uptick in Covid-19 hospitalization rates related to the JN.1 subvariant.

According to official statistics, 302,100 people in Germany were infected with JN.1 up to December 20, an increase from 110,000 on October 20 and 195,000 on November 20.

Dasgupta said India was also experiencing an uptick in cases, especially in the states of Kerala and Karnataka, where authorities have intensified disease surveillance and are advising people to take appropriate measures.

But it's not only in Germany and India said Ziyad Al-Aly, an expert in public health based at Washington University in St. Louis.

"The situation is becoming more concerning. [JN.1] seems to be taking over nearly everywhere in the world," said Al-Aly. "In Singapore, the numbers are really high. In the US, cases and hospitalizations are also rising."

How are Covid-19 infection rates being tracked?

The true infection rates of Covid-19 are likely to be higher than those reported due to a lack of widespread testing.

Most countries stopped systematic reporting of Covid-19 test results in late 2022 or early 2023, and fewer people are tested anyway. So, it's difficult to know the true rates of Covid-19 around the world.

The primary source of data for Covid-19 rates is now wastewater surveillance.

"It's not an ideal method, but it's a pretty decent indicator of how much virus is circulating around the community," said Al-Aly.

Wastewater surveillance can't test individual rates of Covid or indicate who has it, but public health experts can use this data to track viral load over time and predict a general level of risk.

Another way governments are tracking Covid-19 is through the number of hospitalizations due to the virus — that tracks the most severe cases.

"Tracking both wastewater and hospitalization is quite informative. We saw an uptick in wastewater Covid several weeks ago, and then saw higher rates of hospitalization literally two weeks later. So, it's working," said Al-Aly.

How can I protect myself from Covid-19?

One of the most important things you can do, said Al-Aly, is to keep up with vaccinations.

"It's very important for people to get an updated vaccine, and also to get vaccinated for other infectious agents like flu and RSV if you qualify," Al-Aly told DW.

The good news, said Al-Aly, is that the latest generation of vaccines are effective against the JN.1 subvariant.

However, boosters are not available everywhere around the world, said Dasgupta: "India has discontinued the boosters. In fact, the coverage of the third booster dose has lagged far behind the first two doses."

The WHO recommends wearing a mask in public spaces or skipping social gatherings if you feel ill — that can help reduce the spread of the virus.

What if I test positive for Covid-19?

"The first thing you should do is see if you qualify for antiviral medication, if you test positive. We know antivirals also reduce the risk of severe disease that is to hospitalization risk of death and also risk of long Covid," said Al-Aly.

Antiviral medication is particularly effective for people at risk of severe Covid infection — older adults, immunocompromised individuals, and people with heart diseases or lung diseases.

"And, obviously, you know, isolate," Al-Aly said. "You don't want to transmit it. So don't show up to that Christmas party. Work from home or don't work at all. It's the same common-sense procedures as when we first started [with the pandemic]."

To prevent infections and severe disease, the WHO advises:

-- wear a mask in crowded, enclosed areas

-- cover up coughs and sneezes

-- wash your hands regularly

-- stay up to date with Covid and flu vaccinations, especially if vulnerable

-- stay home if ill

-- get tested if you have symptoms