The swine flu pandemic has forced Saudi Arabia to ban old people and children from making the pilgrimage to Mecca.
Anjum Rahman of the Islamic Women's Council of New Zealand told Morning Report on Friday that people who had been planning to go on the pilgrimage in November will be devastated.
The chronically-ill are also covered by the ban agreed at emergency talks in Cairo with the World Health Organisation.
The hajj draws millions of people to Saudi Arabia each year and Ms Rahman said the health facilities there are incredible.
She said the pilgrimage sees about 3.5 million people squeeze into a relatively small area and authorities know they cannot control the spread of a virus in that setting.
At least two million people took part in last year's Hajj.
Church considers halting sharing of wine
The Archbishop of Canterbury has recommended that the Church of England should suspend the sharing of wine during communion because of the swine flu pandemic.
Dr Rowan Williams says priests should dip communion wafers in the chalice, or communion cup, if people still want to receive the wine.
Other churches in Britain have made similar decisions to reduce the risk of spreading the virus.
Britain has the highest numbers of people in Europe affected by swine flu. The number of new cases has doubled by 100,000 in the past week and 26 people have died from the virus since the outbreak began.
Sufferers are now able to access drug prescriptions over the phone and the internet without seeing a doctor.
Swine flu has now spread to 160 countries, killing about 800 people, but its behaviour so far has not changed, the World Health Organisation said on Friday.