Hong Kong’s present policy is 70 per cent of the population receiving two doses of the Covid-19 vaccine so as to attain herd immunity. This is based on the idea that 70 per cent coverage will form a protective shield for the remaining 30 per cent who cannot be, or have not been, vaccinated. However, recent happenings in Hong Kong and elsewhere suggest the herd immunity strategy is not working to control the outbreak of the Delta variant. A young, fully vaccinated Hongkonger who returned from the United States tested positive for Covid-19 and was found to be highly infectious. Recent research in the US indicates a similar phenomenon. However, in both cases, researchers have found that the vaccination is still useful in protecting people from serious illness and death. Thus, people who have been fully vaccinated can still be infected and they might not show any sign of illness, but they have a much better resistance against serious illness. Most importantly, the theory that herd immunity can be attained after 70 per cent of the population has received both vaccine doses is not being borne out. Before a better vaccine can be produced, the only alternative for Hong Kong at present is to get at least 95 per cent of the population to receive two doses of the vaccine. To attain this goal, a large percentage of the elderly must be encouraged to get vaccinated. In addition, we must urgently study the feasibility of helping children under 12 years old to get vaccinated. In the meantime, precautionary measures such as mask wearing, washing hands and social distancing must continue. Moreover, the need for a 21-day quarantine period for travellers from high-risk areas cannot be overstated. Finally, recent findings and research tend to suggest that with the types of vaccine currently available, anyone receiving both doses can only protect themselves. This is exactly why we need 95 to 100 per cent of the population to be fully vaccinated to attain herd immunity. Dr Wong Hong-yau, Happy Valley US focus on ‘freedom’ hurts public health It is tragic and an international disgrace that the United States is still debating vaccines against Covid-19 as a matter of so-called freedom of choice (“US hospitals sound alarm over Delta surge”, August 9 ). In many countries around the world, including in Europe, the pandemic is treated as an emergency where decisions are made by public health bodies and experts, such as Dr Anthony Fauci , director of the US National Institute of Allergy and Infectious Diseases. Former president Donald Trump’s repeated insistence that Covid-19 would “go away”, as if it was the flu, did not help matters. Vaccinations should not be a choice when they are needed to control the spread of infection. China, with its one-party communist government, has had much better success at controlling the spread of Covid-19. It views anti-epidemic measures not as a matter of personal choice but one of national survival. Gerald Heng Snr, Washington Sports can provide Indian youth a better life There is widespread joy among Indians over the country winning seven medals at the Tokyo Olympics . There has also been bitter disappointment when Indian participants lost out on medals by a whisker, as in the bronze medal match in women’s hockey and golf. The joy and pain were palpable in the country. This is the first time that I have seen Indians involved minute-by-minute in the progress of our Olympians. When the Indian women’s hockey team lost to the British team in the bronze medal match, the players sank to their knees and wept. The hearts of all Indian television viewers went out to them. This new mass involvement of Indians in the Olympics is heartening as it will encourage more Indian youngsters to train in sports and win medals for themselves and their country. The ample rewarding of the medal winners by various state governments and private institutions will also motivate more young people. For instance, Neeraj Chopra, who won a gold medal in the javelin throw, has already been awarded about US$2 million in the first 36 hours of his victory, even before he returned to India. The winning of a solitary gold medal by an Indian athlete led to widespread celebration across the country. India was starved of a gold medal before Chopra earned it and became a national hero within a few seconds. For a country with a population of more than 1.3 billion people, seven medals are really not that many. Hopefully, governments will allocate more funds to training institutions, hire the best coaches and provide players with holistic training. The training institutions should have comfortable residential facilities. Youngsters should be encouraged to pursue sports as a profession, not merely a pastime or a hobby. Sports should become a form of livelihood in India and other developing countries with massive unemployment. For this, sports should be recognised as an industry by itself and should be free of politics. Rajendra Aneja, Mumbai Outrage over Korean ‘shortcut’ campaign misplaced It was recently reported that South Korean archer An San , who won three Olympic gold medals in Tokyo, was criticised for her short hair, which some men found offensive because they associated it with feminism and consider feminists to be man-haters. A feminist woman, Han Ji-young, created a #women_shortcut_campaign on Twitter in response. The reaction to An’s hair is an indication of the status of women in Korean society. For example, Korean women earn only about two-thirds of men’s salaries – one of the highest gender pay gaps among developed nations. Feminism is not about disrespecting men but rather a campaign for gender equality. The “shortcut” initiative is simply a way to raise awareness of the subordination of women, not an attack on men. Natalie Leung, Tseung Kwan O