FRANK JORDANS Associated Press Writers GENEVA (AP) — Drug manufacturers won't be able to start making a swine flu vaccine until mid-July at the earliest, months later than previous predictions, the World Health Organization said Tuesday. The disclosure that making a swine flu vaccine is proving more difficult than experts first thought came as U.N. Secretary-General Ban Ki-moon and WHO chief Dr. Margaret Chan met Tuesday with representatives from up to 30 pharmaceutical companies to discuss the subject. Health officials from around the world are attending WHO's annual meeting in Geneva this week to discuss the outbreak that has infected 9,830 people in over 40 countries, killing 79 of them. According to vaccine experts convened by WHO last week, swine flu virus is not growing very fast in laboratories, making it difficult for scientists to get the key ingredient they need for a vaccine, the "seed stock" from the virus. The flu experts said vaccine manufacturers will not be ready to produce a swine flu vaccine until mid-July at the earliest, the agency reported Tuesday on its Web site. Previously, WHO officials had estimated that production could start in late May. Experts also found no evidence that regular flu vaccines offer any protection against swine flu. Vaccine experts estimated under the best conditions, they could produce nearly 5 billion doses of swine flu vaccine over a year after beginning full-scale production. In that situation, the U.N. might have access to up to 400 million doses for poor countries. The rest of the vaccines would presumably go to wealthy contras who have already signed deals to get the pandemic vaccine as soon as it is available. Mass producing a pandemic vaccine would be a gamble, as it would take away manufacturing capacity for the seasonal flu vaccine that kills up to 500,000 people each year. Some experts have wondered whether the world really needs a vaccine for an illness that so far appears mild. Chan said Monday it would be impossible to produce enough vaccine for all 6.8 billion people on the planet. That suggests a possible global scramble where rich countries outbid poorer nations for the vaccine, leaving them unprotected against the virus. "It is absolutely essential that countries do not squander these precious resources through poorly targeted measures," said Chan. Unlike other countries such as Britain, the United States has so far refrained from reserving its share of any new vaccine. "At this point we have not placed orders for vaccine," U.S. Health and Human Services Secretary Kathleen Sebelius told reporters in Geneva. "There is still so much uncertainty about this virus that it is really premature for us to even make a determination of how many people would appropriately be vaccinated, in what order, how many doses would be required, and at what point." These are the issues Ban and Chan will discuss with vaccine makers, believed to include top producers Sanofi-Aventis, GlaxoSmithKline and Baxter International as well as drugmakers from developing countries. On Monday, dozens of governments lobbied WHO to tread carefully before next raising its swine flu alert to the highest pandemic level of phase 6. The level currently stands at phase 5 — saying a global outbreak is "imminent." Britain, Japan, China and others said Monday that declaring a global outbreak could cause unnecessary panic and confusion, especially since the virus has turned out to be less deadly than feared. The expert group emphasized that WHO's declaration of a pandemic should not automatically force vaccine makers to switch from making regular flu vaccine to pandemic vaccine. In addition, they said even if swine flu vaccine production began, that did not mean that countries should start immunizing large groups of people. The experts told WHO that it should come up with targeted advice on which groups of people need the vaccine the most and should get it first. They also planned to meet again in several weeks to decide whether large-scale production of swine flu vaccine should begin. Since the outbreak began last month, 79 people have died from the disease — 72 in Mexico, five in the U.S., one in Canada and one in Costa Rica, WHO says. Another U.S. death — that of a 16-month-old — is being investigated for swine flu.