Thousands of cases of asthma, bronchitis and pneumonia linked to air pollution are making the NHS winter crisis worse, the prime minister has been warned.
A group of 175 doctors and health professionals have written to Boris Johnson describing what they call a "public health crisis" with wards and GP surgeries clogged up by patients with respiratory complaints - conditions made worse by poor air quality.
Can you still have lung problems with a normal pulmonary function test?
Follow up doctors & Respiratory physio 
Hospitalised with covid, how long to get off oxygen and released?
After years of being careful... 
Oxygen and100 yard challenge
