Difference Between Pneumonia and Typhoid

Pneumonia and typhoid are infections and have a few common symptoms such as high fever, malaise, loss of appetite, and headache; but they differ in many aspects in terms of disease history, cause, mode of transmission, systems involved, signs and symptoms, and treatment. Preventive measures include vaccination in both conditions.

Pneumonia is an acute infection of the lung tissues, affecting more frequently the children and elderly. It is generally caused by bacteria (streptococcus pneumoniae, mycoplasma pneumoniae, Chlamydia pneumoniae, and Haemophilus influenzae), virus (respiratory syncytial virus, influenza A, and influenza B), fungi, protozoa, and occasionally due to regurgitation of stomach contents into the lungs. Pneumonia may be a community- or hospital-acquired infection. Risk factors include underlying lung infections, immunocompromised status, cigarette smoking, systemic diseases such as diabetes mellitus, liver cirrhosis, and heart diseases, or surgery in the recent past (especially those involving mouth, throat, and neck). Symptoms include cough, chest pain, an initial dry, painful cough that later becomes productive, wheezing, fever with chills and rigors, vomiting, and difficulty in breathing. Investigations are done to confirm the diagnosis radiologically and microbiologically, assess the severity of the disease, rule out other diseases that mimic pneumonia, and for early detection of complications, if any. A chest X-ray shows characteristic shadows. A complete blood count, arterial blood gases, and blood and sputum cultures are done; as in acute infections, the C-reactive protein in the blood will be abnormally high. A CT scan, bronchoscopy, a pleural fluid aspiration and culture will be considered if pneumonia is unresponsive to initial treatment. Treatment includes antibiotics, either oral or systemic, and maintenance to keep a fluid balance. Expectorants promote liquefaction of sputum, which in turn will be coughed out. Antipyretics such as paracetamol alone may not be sufficient, necessitating the use of painkillers. Oxygen therapy may be required in a few patients. Serious complications such as fluid collection in the lungs, lung collapse, formation of lung abscess, and the spread of infection to other tissues may occur. If untreated, the pneumonia may result in respiratory failure and death.

Typhoid is a bacterial infection, frequently seen in developing countries, caused by salmonella typhi with transmission through a fecal-oral route, i.e., ingestion of food or water contaminated with the urine or feces of infected people or asymptomatic carriers. People infected with typhoid bacilli who sometimes may not show clinical features are termed as “asymptomatic carriers,” and they may shed the bacilli for a long term, in turn infecting others. Salmonella typhi (S. typhi) enters the body through the gastrointestinal tract, multiplies in the bloodstream, and later spreads to the liver and gallbladder. It is a multisystem disorder; symptoms include high fever associated with malaise, headache, vomiting, loss of appetite, abdominal pain, diarrhoea, body aches/muscle pain, and enlargement of the liver and spleen; small red spots on the abdomen and chest known as “rose spots” may appear in a few patients. Additionally, there may be cough, bleeding from the nose, and abdominal distension with pain upon touching. A complete blood count may reveal a high white blood cell count. A blood culture is done in nonconfirmatory cases. The Widal test, which detects antibodies, has to be interpreted cautiously. The ELISA blood test, a fluorescent antibody test, or a stool culture may be required in case of any doubt. Antimicrobials and/or antibiotics are to be administered, which need to be continued for two to three weeks. Repeat blood investigations indicate the clearing of the infection. The adoption of a fat-free diet is advised to reduce the load on the liver and gallbladder. Analgesics, antipyretics, and other drugs are to be avoided. Complications include perforation of a bowel or bleeding. Infection may spread to bones and joints, coverings of the brain, gallbladder, kidney, and heart muscle. Toxic pneumonia can develop.

This condition can be prevented if hygienic measures are adopted. Vaccination is advised for those travelling to regions where typhoid is endemic.