Christmas to avoid a coronavirus spike, the World Health Organisation (WHO) has urged.Lockdown restrictions in the UK are being relaxed over the festive period, along with some other countries in Europe, but world health chiefs are warning people to be careful at family gatherings.The WHO said there is a "high risk" of a resurgence of Covid-19 in 2021 and new guidance issued urged people to avoid "even small indoor gatherings" and to wear face masks when mixing with friends and family outside your household.Experts warned the relaxing of rules could lead to a spike in deaths amid fears of a third wave of coronavirus.The organisation said: "Indoor gatherings, even smaller ones, can be especially risky because they bring together groups of.