COVID-19 insurance policies are increasingly joining passports and sunscreen as vacation staples, creating opportunities for insurers as more countries require mandatory coverage in case visitors fall ill from the coronavirus.

Airline bookings are on the rise in some regions, driving cautious hopes of a revival in summer traffic, but also raising fears among tourist destinations of getting hit with bills should vacationers become stranded by the virus.

More than a dozen countries from Aruba to Thailand require COVID-19 coverage for visitors, with Jordan the latest to consider such protections, organizers of an emergency services plan told Reuters.

The market for all types of COVID-19 travel coverage is estimated to be between $30 billion to $40 billion a year, according to travel insurance consultant Robyn Ingle, with companies like AXA and AIG underwriting protection.

But a surge in demand for COVID-19 coverage also means insurers could be on the hook for big payouts should another wave of infections lead to large numbers of cancellations or tourists getting sick.

“Travel insurance and protection services are taking off at pace with travel as it resumes, said Dan Richards, chief executive for travel risk and crisis management firm Global Rescue.

COVID-19 insurance benefits typically cover treatment up to $100,000, and could include coronavirus testing costs and services like evacuation or local burial or cremation. These benefits, introduced by insurers in mid-2020, are sold either as add-ons or as separate policies with coverage for illness or quarantine.

Jeremy Murchland, president of Indiana-based travel insurance company Seven Corners, said travelers are now “more likely to insure their trips,” as more countries require COVID-19 coverage.

A travel insurance plan that includes trip protection, medical expense coverage for COVID-19 and protection for baggage and personal effects typically costs 4% to 8% of the dollar value of the trip, Murchland said.

While the pandemic has battered travel, demand for coverage has created opportunity for the hard-hit insurance industry and a niche to develop new products, companies said.

For example in June, Seven Corners introduced an optional medical travel plan with coverage for coronavirus expenses, Murchland said. By year’s end, the product with coronavirus coverage generated about 80% of total medical travel plan sales.

Seven Corners also saw a 20% rise in travelers buying highly priced “cancel for any reason” policies in 2020. The policies cover cancellation costs related to the virus.

Some countries have mandated travel insurance for incoming visitors – either by including it in their entry or visa fees or by requiring proof of coverage, said insurer World Nomads.

Jordan is evaluating whether to require a mandatory flat fee for visitors as part of a program from Global Rescue and the Global Travel and Tourism Resilience Council, said council co-chair Taleb Rifai. The program, which costs up to $100 per person, covers certain disasters and illnesses like COVID-19.

Jordan’s Tourism Bureau was not available for comment.

It is not clear how coverage demand will evolve as many more people become inoculated against the coronavirus with vaccines.

Frank Comito, a special advisor to the Caribbean Hotel and Tourism Association, said some budget travelers have complained about mandatory coverage. And some countries could discontinue or relax the requirement as “we move away from the pandemic.”

Rifai, former secretary general of the UN’s World Tourism Organization, said he expects countries will continue requiring coverage as the vaccines “will take years” to roll out globally.