STDs from kissing

A kiss is usually an exciting, wonderful and, occasionally, unexpected experience; but we must never forget that passionate kisses are also an easy and efficient way to spread infectious diseases.

Can diseases be transmitted through kisses?

Within the multiple infection pathways we find oral transmission, which includes the spread of bacteria through saliva, food or drinks.

When we kiss someone, the swallowing action of the tongue allows contaminated saliva to reach the throat. From there, it penetrates the body and produces infections: such as infectious mononucleosis (kissing disease), caused by the Epstein-Barr virus (EBV), and cytomegalovirus (CMV).

Bacteria, such as Streptococcus, can also adhere to the inside surface of the cheeks, mouth, tongue or teeth and cause infections of the gums and throat (tonsillitis).

The mucous surfaces of the respiratory tract have similar tissue and share equal spaces (nose, mouth and throat). Therefore, saliva microbes can spread to the respiratory tract and cause colds and other diseases of the upper respiratory tract.

Natural antimicrobial mechanisms of the mouth

Saliva plays an active role in cleansing and rinsing away because it is a continuous fluid. Dehydrated people have almost four times more bacteria in their mouth due to decreased salivary flow. Other defenses in saliva include antibodies and antimicrobial proteins (eg lysozymes). In addition to the normal oral flora (the ‘good’ bacteria that prevent the growth of the ‘bad’ bacteria).

Diseases spread through saliva also occur when the natural resistance of the mouth is reduced. For example, gum disease is common when there is a deficiency of vitamin C. Candidiasis is also more common in long term antibiotic treatments

Diseases that are spread through saliva

Infectious mononucleosis

It is an infection usually caused by Epstein-Barr virus and, rarely, by cytomegalovirus (CMV). It spreads through saliva and is usually called the ‘kissing disease’. Although it can appear at any age, it is more frequent in adolescents and young adults.

Its symptoms usually include fever, sore throat and swollen lymph nodes.

Symptoms relief is the primary treatment goal. It includes rest, hydration, painkillers and fever and gargles with warm water and salt for the sore throat.

Most people get better in 2 to 4 weeks. Serious complications (such as inflammation of the spleen) are rare, although the feeling of tiredness may persist for 2 or 3 months after the disease is over.

Herpes

There are two types of herpes simplex virus (HSV):

type 1 (HSV-1), usually oral,
and type 2 (HSV-2) or genital.

Oral infection, also called cold sores or fever blisters, is caused by herpes simplex virus type 1 (HSV-1) which spreads through active lesions on the lips or near the mouth.

It is contagious at all stages, but mainly when the sores are ulcerated and draining fluid.

It can be caused by kissing, but also by sharing utensils and glasses.

It may appear only once in isolation or more commonly as a recurrent infection.

Initially, there is a burning or itching sensation, followed by small blisters that burst to leave open sores, on which later appears a scab. After a few days it heals and rarely leaves scars.

Although, so far, it has no cure, its effective treatment helps control the disease.

To reduce the risk of acquiring it: a quick visual inspection of the other person’s lips should be done for obvious injuries and ask about any apparent injury. While there are obvious lesions, mouth or mouth and orogenital contact should be avoided. Herpes may spread to the genitals causing genital herpes. Although the process could also be reversed, the transmission of HSV-2 from a genital infection to the mouth is very rare.

HIV and hepatitis

Infection with Human Immunodeficiency Virus (HIV) and hepatitis B (HBV) are sexually transmitted and blood borne diseases. Although the presence of HIV in saliva has been proved, its concentration is so low that it cannot cause an infection. In fact, no case of transmission by this route has ever been reported.

In contrast, it has been documented for hepatitis B. Here contagion can occur when there are bleeding wounds in the mouth or periodontal disease that causes bleeding gums. Hepatitis A requires fecal exposure (from contaminated water or anilingus) and hepatitis C requires exposure to blood.

Are diseases that are spread through saliva sexually transmitted infections?

The most common infections transmitted by kissing are not considered STIs (sexually transmitted infections). However, in summary, the most common are infectious mononucleosis, the common cold, some stomach parasites and strep throat infection.

Regarding the acquisition of ITS:

Although some germs have been found in saliva, mouth-to-mouth kisses usually only transmit herpes, as opposed to oral sex, which can spread many STIs, such as gonorrhea, syphilis, genital condylomas, chlamydia and hepatitis A, B and C.

STDs from kissing