* Pregnant women advised not to travel to Zika areas
* Rio Olympics insured against cancellation
* Sponsors, hotels may not be
* Question mark over whether Zika is communicable disease
By Noor Zainab Hussain and Carolyn Cohn
LONDON, March 18 (Reuters) - Organisers of rock concerts and conferences in Latin America or fringe events at the Rio Olympics beware: if you still need insurance to cover cancellation due to the Zika virus, it's probably too late.
The International Olympic Committee (IOC) should be fine. It took out cancellation insurance for this August's games in the Brazilian city years ago, long before the mosquito-borne virus spread from the country through the Americas.
Anyone else who acted early is probably also safe. "Existing policies are unaffected and cover is provided," said Gary Flynn, at insurance broker JLT Specialty.
But organisers still seeking protection are finding clauses that block any payout, should their event be called off due to the Zika outbreak. "Insurers are now excluding this peril from any new cancellation policy for events in an affected area," said Flynn, who is JLT's practice leader for sport federations.
Insurers said they were unaware of any events being cancelled because of Zika, but underwriters are not taking any chances about the possible impact on sponsors or hospitality providers, as well as on other events in the region.
Much about Zika remains unknown and a link with microcephaly in babies, a condition defined by unusually small heads that can result in developmental problems, has yet to be proved.
Nevertheless, the World Health Organization has advised pregnant women against travelling to areas affected by the outbreak, due to the potential risk of birth defects.
Some organisations and countries have gone further. The United States has told sports federations that athletes and staff concerned for their health should consider not going to the 2016 Olympics.
The IOC says it has bought cancellation insurance worth about $800 million for the Olympics, with a premium of about $13 million.
Cover for such big events is bought at least five years beforehand, underwriters say. But sponsors, hotels and bar owners or people running venues such as fan parks - where sports enthusiasts can watch events on giant TV screens - may not yet have bought insurance, they add.
The 2014 FIFA World Cup in Brazil had an estimated event cancellation cover including television rights and sponsorship of $1.25 billion, according to underwriter Beazley Plc. Other cancellation cover for hotels or hospitality providers added around $600 million, it said. (bit.ly/1S1QSoP)
With South America a popular destination for international rock bands, concerts are among the events in affected countries which face Zika exclusion clauses, along with trade shows, exhibitions and conferences.
"We do consider applying Zika-specific exclusions when we see events taking place in certain areas of the world like South America," said Jeremy Cooke, contingency underwriter at insurer ProSight.
Theoretically cover may still be available for Zika cancellations, but insurers say customers would have to pay a "significant" premium - meaning the cost would probably be prohibitive.
The Lloyd's of London insurance market is the global leader in specialist insurance such as event cancellation, or contingency.
The UK contingency class is worth 150-200 million pounds ($215-$290 million) in premiums, according to JLT, with exposure to billions of dollars of losses.
Alan Norris, head of contingency at Talbot Underwriting, said underwriters became concerned about communicable diseases after the 2001 foot-and-mouth disease outbreak among farm livestock in Britain.
As the disease spread rapidly, people were discouraged from visiting the countryside, leading to the cancellation of many events and badly hitting tourism in particular.
The insurance industry has since seen claims arising from the outbreak of the severe acute respiratory syndrome (SARS), including from Singapore and Toronto, as well as avian and swine flu.
The result is that contingency policies normally contain a blanket exclusion for communicable diseases - those which are spread between people or from animals to humans.
The only possible element of doubt for existing policyholders is the definition of Zika.
Insurers are divided on whether the virus, being transmitted by mosquitoes, can as yet be classified as a communicable threat, explaining the need for separate Zika exclusion clauses.
"I personally would always view it as a communicable disease, despite some wordings referring to airborne pathogens or other characteristics that do not fit the Zika virus," Cooke said.
As ever, everything will depend in the end on the small print in each policy.
And insurers said that even if companies' policies do cover cancellation due to Zika, cancellation would have to be out of an organiser's control for cover to apply.
"It must be a necessary cancellation," said Elizabeth Seeger, contingency underwriter at insurer Hiscox. "An insured (organiser) can't choose to stop their event." ($1 = 0.6920 pounds) (Additional reporting by Karolos Grohmann and Richa Naidu; editing by David Stamp)