Complications of whooping cough
Complications are more likely in babies under 4 months.
Whooping cough can lead to pneumonia occasionally in older children and adults.
Whooping cough does not cause long term lung damage.
Bruising in the skin and cracked rib can happen, also hernias.
Only a small number get complications from whooping cough. About 1% of clinically diagnosed cases in my experience. Of course, if you only count hospital cases or laboratory proven cases, (which are going to be the more severe cases,) then the proportion of those with complications is greater. But you can only get a true perspective if ALL cases that occur are counted.
This is where many published figures are misleading and may lead you to believe that whooping cough has a high rate of complications. Because whooping cough goes unrecognised much of the time official figures tend to exaggerate the severity and underestimate the incidence (the number of cases).
1 in 100 gets pneumonia.
In my published study of 500 consecutive cases in an English village over 20 years, only 1 in 100 developed significant complications such as pneumonia. NHS website page on pneumonia
Very young babies can die of whooping cough (1 in 100 approximately in developed countries).
The worst complication is death. This is rare except in young babies for whom it is a more exhausting illness than some can stand. In babies it can lead to respiratory failure, convulsions and coma from encephalopathy.
It is thought that some very young babies who get it, do not cough at all, but simply stop breathing.
Stopping breathing usually comes after a bout of coughing. In the United Kingdom one child in 100 who gets it under the age of six months dies from it. In older children death is very rare, perhaps 1 in 200,000 cases. In the underdeveloped world, the mortality is vastly greater.
There are minor complications that are often described but usually occur only in the most severe cases. These are; bleeding over the white of the eye (subconjunctival haemorrhage), blood spots in the skin (petechiae), tearing of the ligament at the base of the tongue and umbilical hernia.
All these are caused by congestion of blood or the strain of coughing, retching and vomiting. If you watch the videos and listen to the sound files on the symptoms page you will understand how the severity can cause these traumatic effects.
Textbooks often give misleadingly exaggerated pictures of complications.
All these things are described in textbooks and reading them gives the impression they are very common.
Although I know these things do occur, none of my patients (in my family practice) has yet, to my knowledge, developed any of these congestion caused complications. I have seen pictures of them in the emails that people have sent me over the years.
Injury from fainting after a paroxysm.
Some people faint with paroxysms and may make involuntary jerking movements resembling a fit. They may have no recollection of the faint, but unlike a true fit, they will usually remember the events leading up to it.
Sudden infant death syndrome.
It is suspected that undiagnosed whooping cough could possibly be the cause of some cases of sudden infant death syndrome (SIDS). This probably happens less now than in the past, since whooping cough is now recognised as a cause, and tests are now available to detect it more easily.
No long term effects.
Whooping cough does not cause long term lung damage. (Young babies who have been very ill with it might may be an exception).
Some years ago people thought that whooping cough led to bronchiectasis, a condition in which the main air passages in the lungs become enlarged and distorted. This allows sputum to accumulate and fester, causing the sufferer to have a chronic productive cough and susceptibility to more severe lung infections and general debility. Most cases of bronchiectasis have probably not been caused by whooping cough, but by previous pneumonia. I do not know of any evidence that uncomplicated whooping cough causes bronchiectasis.
Does not cause asthma. But asthmatics are more susceptible to whooping cough.
More people who have whooping cough have asthma than those who have not had whooping cough. Whooping cough does not cause asthma. It just so happens that people with asthma are more susceptible to it.
Voice changes been recognised as a complication for a long time. The letter below is from an ENT specialist in 1932.
He also makes us realise whooping cough has always been recognised to occur in adults. This letter was written long before there was any immunization against whooping cough.
A few people with whooping cough become hoarse or notice their voice changes. Singers may find they cannot sing as before. This usually resolves itself as the cough goes but occasionally it seems that the voice does not fully recover. Genny DiStasio found a letter (below) in an old journal (Dr. Dan McKenzie, August 1932, Journal of Laryngology and Otology, Volume 47, Issue 8, p. 546) that seems to suggest it was common knowledge in the days before immunization.