Differences between bacterial and viral infection

While bacteria and viruses can both cause mild to serious infections, they are different from each other. This is important to understand, because bacterial and viral infections must be treated differently. Misusing antibiotics to treat viral infections contributes to the problem of antibiotic resistance.

Bacteria vs viruses

Bacteria and viruses are too tiny to be seen by the naked eye, can cause similar symptoms and are often spread in the same way, but that’s where the similarities end.

A bacterium is a single, but complex, cell. It can survive on its own, inside or outside the body.

Most bacteria aren’t harmful. In fact, we have many bacteria on and inside our body, especially in the gut to help digest food.

Viruses are smaller and are not cells. Unlike bacteria, they need a host such as a human or animal to multiply. Viruses cause infections by entering and multiplying inside the host’s healthy cells.

                                        

Bacterial vs viral infection

As the names suggest, bacteria cause bacterial infections, and viruses cause viral infections.

It is important to know whether bacteria or viruses cause an infection, because the treatments differ. Examples of bacterial infections include whooping cough, strep throat, ear infection and urinary tract infection (UTI).

Viral infections include the common cold, flu, most coughs and bronchitis, chickenpox and HIV/AIDS.

It can be difficult to know what causes an infection, because viral and bacterial infections can cause similar symptoms. Your doctor may need a sample of your urine, stool and blood for a ‘culture’ test to have the bugs identified under a microscope.

                                 

Types of Fever

Fevers caused by infection are especially common in people who have traveled to developing countries or parts of the world where health care resources and sanitation are limited. Any international traveler who develops fever in the weeks after returning home should be evaluated.

Malaria

                                            

Malaria is a parasitic disease spread by mosquitoes in tropical and subtropical climates. It causes a high fever, chills, and flu-like symptoms. It can also lead to anemia, a condition in which the body lacks red blood cells, causing weakness or tiredness. 

The disease is spread when a mosquito infected with a malaria parasite bites a person, depositing the parasite into the bloodstream. The parasite then travels to the liver, where it multiplies. These parasites infect red blood cells, which burst and go on to infect more red blood cells in the body.

Dengue 

Dengue fever is a viral infection that causes flu-like symptoms. It occasionally develops into a potentially lethal infection called dengue hemorrhagic fever. The infection is passed to humans through the bite of specific types of mosquitoes infected with one of four closely related dengue viruses. 

Dengue causes a fever of 104 degrees or higher, severe headache, severe pain behind the eyes, joint pain, muscle and bone pain, rash, and, sometimes, mild bleeding in the gums or from the nose. Generally, in younger children and those experiencing a first dengue infection, the illness is milder than in older children and adults.

                                              

Typhoid Fever

Typhoid fever is a life-threatening illness caused by the bacterium Salmonella Typhi. It is spread by ingesting food or water contaminated with sewage or feces infected with these bacteria. People with typhoid fever carry the bacteria in their bloodstream and intestinal tract.

After Salmonella Typhi bacteria are ingested, they multiply in the intestinal tract and spread into the bloodstream. The body reacts with fever and malaise, but abdominal pain and headache can also occur.

If left untreated, typhoid fever can be fatal. It begins 7 to 14 days after ingestion of the bacteria, peaks at 103 to 104 degrees, and may be accompanied by small, rose-colored spots on the skin of the chest and abdomen.

Typhoid fever occurs worldwide, primarily in developing nations with poor sanitation, where hand washing is less common and water is likely to be contaminated with sewage. 

Chikungunya

Chikungunya is a viral disease spread by infected mosquitoes that causes fever and severe joint pain, especially in the small joints of the hands and feet. It can also cause muscle pain, fatigue, headache, nausea, and a rash. 

                                           

Chikungunya may cause eye problems such as redness or blurred vision, neurological complications such as facial paralysis and Guillain–Barré syndrome, and gastrointestinal symptoms such as nausea and vomiting.