DUBAI -- The world's estimated 1 billion smokers are likely to experience more severe symptoms of coronavirus and should quit the toxic habit, warn health officials. The US Centers for Disease Control and Prevention and the World Health Organization have warned that smokers, as well as those with diabetes, heart disease, or chronic lung disease, are at a greater risk of developing severe complications. People who smoke are typically at higher risk of contracting respiratory tract infections such as lung and chest infections as smoking can damage the lungs and airways. COVID-19 attacks the respiratory system, making breathing difficult. Although not everyone who contracts the disease experiences breathing difficulties, they may be more severe in smokers. "There has never been a more important time to stop smoking, not only for your own health, but to protect those around you," said Prof. John Newton, Public Health England's director of health. More research is needed to know the exact relationship between smoking and coronavirus, but one initial study from China gives indications of how coronavirus more heavily impacts smokers. In Wuhan, the city in China where coronavirus originated, smokers who became infected with the disease were 14 times more likely to develop more severe symptoms. In China more broadly, a study of 1,099 COVID-19 patients of which 173 had severe symptoms showed that 16.9 percent of those with severe symptoms were current smokers, and 5.2 percent had previously smoked. Of those patients with less severe symptoms, 11.8 percent were current smokers and 1.3 percent smoked previously, a study published in the New England Journal of Medicine found, according to Forbes. Among those who required intensive care, ventilation, or who died, 25.5 percent were current smokers. Around the world, there are 942 million men and 175 million women ages 15 or above who currently smoke, the Telegraph reported. Men seem more likely to die from coronavirus, and some researchers have suggested that there may be a link between the death rate for men and their higher propensity to smoke and drink. Despite the risks and warnings, cigarette sales have not fallen. Quartz reported on April 3 that instead sales had seen a slight 1.1 percent uptick over the last week of March. However, that shift could be explained by the fact that people have been stocking up on cigarettes with lockdowns in place, as similar trends are visible in alcohol sales. -- Al Arabiya English