Breastfeeding women (WHO, UNICEF , 2025) , Mastitis and Injury caused Mastitis

1. Introduction

Breastfeeding has long been recognized by global health authorities such as the World Health Organization (WHO) and the United Nations Children's Fund (UNICEF) as one of the most crucial interventions for enhancing child survival and promoting maternal health. According to Dr. Tedros Adhanom Ghebreyesus, Director-General of the WHO, and Catherine Russell, Executive Director of UNICEF, breastfeeding not only boosts the immune systems of infants but also fosters cognitive development and reduces the risk of chronic diseases later in life (WHO & UNICEF, 2023, 2025). However, despite its benefits, breastfeeding is not without complications. One of the most common and painful conditions associated with lactation is mastitis — an inflammatory condition of the breast tissue that can be exacerbated or caused by bacterial infection.

Breastfeeding is one of the most effective ways to ensure a baby’s health, development, and survival in the earliest stages of life. It acts as their first vaccine, providing protection against diseases including diarrhoea and pneumonia.

Investing in breastfeeding is an investment in the future, yet only 48 per cent of infants under six months are exclusively breastfed – well below the World Health Assembly target of 60 per cent by 2030. This is due to the overlapping challenges for new mothers, health workers, and health systems. 

Millions of mothers around the world do not receive timely and skilled support in a healthcare setting when they need it most.

Only a fifth of countries include infant and young child feeding training for the doctors and nurses who care for new mothers. This means the majority of the world’s mothers leave hospitals without proper guidance on how to breastfeed their babies and when to introduce complementary feeding.

In many countries, health systems are too often under-resourced, fragmented, or poorly equipped to deliver quality, consistent, evidence-based breastfeeding support.

Investment in breastfeeding support remains critically low even though every dollar invested generates US$35 in economic returns.

As we mark World Breastfeeding Week under the theme, “Prioritize breastfeeding: Create sustainable support systems”, WHO and UNICEF are calling on governments, health administrators, and partners to invest in high-quality breastfeeding support, by:

  • ensuring adequate investment in equitable, quality maternal and newborn care, including breastfeeding support services;
  • increasing national budget allocations for breastfeeding programmes;
  • integrating breastfeeding counselling and support into routine maternal and child health services, including antenatal, delivery, and postnatal care;
  • ensuring all health service providers are equipped with the skills and knowledge required to support breastfeeding, including in emergency and humanitarian settings;
  • strengthening community health systems to provide every new mother with ongoing, accessible breastfeeding support to for up to two years and beyond; and
  • protecting breastfeeding by ensuring that the International Code of Marketing of Breast-milk Substitutes is applied in all health facilities and systems.

Strengthening health systems to support breastfeeding is not just a health imperative, it is a moral and economic imperative. WHO and UNICEF remain committed to supporting countries to build resilient health systems that leave no mother or child behind.  ( WHO, UNICEF 2025) 

2. Definition and Epidemiology

Mastitis is defined as an inflammation of the breast tissue that may or may not be accompanied by infection. It most commonly occurs in lactating women, typically within the first six weeks postpartum, but can appear at any time during the breastfeeding period (Amir, 2014). The condition affects approximately 10–33% of breastfeeding women globally (Jahanfar et al., 2013).

Non-infective mastitis can develop from milk stasis, engorgement, or blocked ducts, while infective mastitis involves microbial infiltration, typically through skin lesions such as cracked nipples. It can progress to breast abscess if not treated promptly.

3. Pathophysiology

The underlying mechanism of mastitis often begins with milk stasis, which may be due to infrequent feeding, poor latch, or nipple trauma. Accumulated milk can lead to increased intra-alveolar pressure and local inflammation, creating an environment conducive to bacterial growth (Kvist et al., 2004). When bacteria gain entry — usually through damaged skin or via the infant’s mouth — they colonize the stagnant milk ducts, leading to infective mastitis.

4. Causative Bacteria

The predominant pathogen implicated in infective mastitis is Staphylococcus aureus, including methicillin-resistant Staphylococcus aureus (MRSA) in some cases (Foxman et al., 2002). Other bacteria include:

  • Streptococcus spp.

  • Escherichia coli

  • Corynebacterium kroppenstedtii (often associated with granulomatous mastitis)

  • Coagulase-negative Staphylococci (CoNS)














Source : https://www.rapidmicrobiology.com/news/chromagar-solution-for-mastitis-diagnosis

Recent molecular studies have shown that the breast milk microbiota may also contain beneficial bacteria, and disturbances in this ecosystem can predispose women to mastitis (Boix-Amorós et al., 2016).

5. Staphylococcus aureus

S. aureus is part of the normal skin flora but can become pathogenic under certain conditions. It possesses multiple virulence factors such as protein A, enterotoxins, and biofilm-forming capacity, making it particularly adept at evading the host immune system. MRSA strains are more resistant to standard antibiotics, posing treatment challenges in both community and hospital settings.

6. Streptococcus species

These organisms are less common but can be found in cases where there is prolonged milk stasis or inadequate hygiene. They are generally sensitive to penicillin-class antibiotics.

7. Corynebacterium spp.

Although initially thought to be skin contaminants, Corynebacterium spp., especially C. kroppenstedtii, have been increasingly associated with idiopathic granulomatous mastitis, a rare but chronic inflammatory breast condition that can mimic breast cancer (Taylor et al., 2003).

8. Clinical Features

The presentation of mastitis includes both local and systemic symptoms:

  • Local:

    • Breast pain

    • Swelling and redness (erythema)

    • Heat and tenderness

    • A palpable lump or induration

  • Systemic:

    • Fever >38.5°C

    • Chills

    • Malaise

If the infection progresses, abscess formation may occur, characterized by fluctuance and more severe systemic signs.

9. Diagnosis

Mastitis is primarily diagnosed clinically, based on history and physical examination. Microbiological testing, including milk cultures, may be warranted in recurrent, severe, or antibiotic-resistant cases. Ultrasound imaging can help rule out abscesses.

10. Treatment and Management

The management of mastitis includes supportive measures, antibiotic therapy, and continued breastfeeding or milk expression:

Supportive Measures

  • Frequent and effective breastfeeding or pumping to relieve milk stasis

  • Adequate rest and hydration

  • Warm compresses and massage before feeds

11. Antibiotics

Empirical antibiotic therapy targets Gram-positive cocci, particularly S. aureus. Common choices include:

  • Flucloxacillin or Dicloxacillin (first-line)

  • Cephalexin

  • Clindamycin or Trimethoprim-sulfamethoxazole for penicillin-allergic individuals

  • Vancomycin for MRSA (only if culture confirms)

The CDC and American Academy of Pediatrics recommend a treatment duration of 10–14 days for infective mastitis (Centers for Disease Control and Prevention, 2022).

Continuing Breastfeeding

Contrary to traditional misconceptions, breastfeeding should continue even during mastitis, unless the mother is too ill or an abscess requires drainage. Continued breastfeeding helps drain the affected breast and promotes faster recovery.

Public Health Relevance and Global Context

NICEF's joint 2023 campaign highlighted that only 44% of infants under six months are exclusively breastfed globally, far below the global nutrition target of 70% by 2030. Conditions like mastitis remain a barrier to achieving this target (WHO & UNICEF, 2023).

Prevention

Prevention strategies include:

  • Ensuring proper breastfeeding techniques

  • Avoiding long intervals between feeds

  • Managing nipple trauma

  • Encouraging maternal support groups

  • Promoting early postnatal care

12. Injury and Mastitis

Injury can cause mastitis, particularly when the injury affects the udder tissue of lactating animals (like cows, goats, or even humans) or the breast tissue in women. Mastitis is inflammation of the mammary gland and can be infectious or non-infectious, and trauma is a recognized predisposing factor. 

How Injury Can Cause Mastitis

a. Disruption of the Mammary Tissue Integrity

Injury — whether blunt trauma, bruising, or cuts — can break the natural physical barrier of the skin and the teat canal, allowing opportunistic bacteria to invade the mammary gland.

“Trauma to the udder predisposes the tissue to bacterial invasion by disrupting epithelial integrity and local immune response.”
— Harmon, R.J. (1994). Physiology of Mastitis and Factors Affecting Somatic Cell Counts. Journal of Dairy Science, 77(7), 2103–2112. https://doi.org/10.3168/jds.S0022-0302(94)77153-8

b. Impaired Immune Defense

Injured tissue often has reduced blood flow and compromised immune cell activity, making it easier for bacteria (like Staphylococcus aureus or E. coli) to multiply and colonize.

"Mechanical trauma of the udder may result in localized edema and impaired neutrophil function, favoring the onset of mastitis."
— Schukken, Y.H. et al. (2011). Host–pathogen interactions in mastitis. Veterinary Microbiology, 153(1–2), 245–252. https://doi.org/10.1016/j.vetmic.2011.06.035

c. Direct Inoculation of Pathogens

Open wounds or micro-lesions caused by kicking, poor milking machine vacuum pressure, or bites (in animals) can directly introduce pathogens into the milk ducts.

“Physical injuries such as biting, stepping, or poor milking hygiene can lead to direct bacterial entry, triggering clinical mastitis.”
— Bradley, A.J. (2002). Bovine Mastitis: An Evolving Disease. The Veterinary Journal, 164(2), 116–128. https://doi.org/10.1053/tvjl.2002.0724

d. Non-Infectious Mastitis from Trauma

Even without bacterial infection, injury can cause aseptic mastitis — inflammation due to damaged tissue, milk leakage into surrounding areas, or bruising.

“Non-infectious mastitis may result from trauma, particularly in heifers or early lactation cows, where inflammation occurs without identifiable pathogens.”
— Jansen, J., et al. (2009). Determinants of farmers’ attitudes towards mastitis treatment. Journal of Dairy Science, 92(7), 3405–3414.

e🧠 Application in Humans

Mastitis in Women

In breastfeeding women, trauma to the nipple or breast (such as infant biting, poor latch, or impact injuries) can also cause mastitis by creating cracks or bruises that harbor bacteria.

"Cracked nipples and blunt trauma predispose lactating women to bacterial mastitis, commonly involving Staphylococcus aureus."
— Amir, L.H. (2014). Breastfeeding and Mastitis: Diagnosis and Management. Australian Family Physician, 43(8), 584–588.

f✅ Summary

FactorRole in Mastitis Development
Physical Injury    Breaches the barrier, introduces pathogens
Tissue Bruising  Reduces immune response, causes inflammation
Open Wounds   Direct entry for bacteria
Non-Infectious Response  Triggers inflammation without infection

g🔬 Conclusion

Yes, injury can cause mastitis — both indirectly (by creating conditions for infection) and directly (by allowing bacterial invasion or causing sterile inflammation). This is well-documented in both veterinary and human medical literature. Mastitis is a common and potentially serious condition affecting breastfeeding women, primarily caused by Staphylococcus aureus and occasionally other pathogens. Prompt recognition and management are essential to prevent complications and ensure continued breastfeeding. As highlighted by WHO and UNICEF, breastfeeding is fundamental to early child development and survival; hence, reducing barriers like mastitis should be a public health priority.

References